Optical analysis system

The present invention determines the amplitude of the major components of an optical signal and detects the optical signal weighted by the first detector and the second spectral weighting function to detect the optical signal weighted by the first spectral weighting function. With respect to an optical analysis system having a second detector.

The present invention also relates to a spectroscopic analysis system having such an optical analysis system.

The present invention also relates to a blood analysis system having such an optical analysis system.

Examples of the optical analysis system described in the opening paragraph are disclosed in US Pat. No. 6,198531.

Known photoanalytical systems are, for example, part of a spectroscopic analysis system suitable for analyzing which components are composed at what concentration in a sample. It is known that when light interacts with a sample, it carries information about the components and their concentrations. Its underlying natural phenomenon is utilized in optical spectroscopy technology, where light from a light source, such as a laser, lamp or light emitting diode, is directed at a sample to produce an optical signal that carries information.

For example, light is absorbed by the sample. Alternatively or in addition, light of known wavelengths interacts with the sample, resulting in the production of light at different wavelengths, for example by the Raman process. The transmitted and / or generated light then constitutes an optical signal, also called a spectrum. The relative intensity of the optical signal as a function of wavelength then indicates the compounds and concentrations contained in the sample.

The optical signal must be analyzed so that the compounds contained in the sample can be identified and their concentrations determined. In known optical analysis systems, the optical signal is analyzed by dedicated hardware with an optical filter. This optical filter has wavelength transmission, that is, it is designed to weight the optical signal by a spectral weighting function given by the wavelength transmission. The spectral weighting function is chosen so that the total intensity of the weighted optical signal, i.e., the light transmitted by the filter, is directly proportional to the concentration of a particular compound. This intensity is conveniently detected by a detector such as a photodiode. For all compounds, dedicated optical filters with unique spectral weighting functions are used. The optical filter may be, for example, a transmissive interference filter that constitutes a desired weighting function.

Understanding the spectral weighting function is essential for successful execution of this analytical method. They are obtained, for example, by performing a major component analysis of a set of N spectra of N pure compounds at known concentrations where N is an integer. Each spectrum has the intensity of the corresponding optical signal at different M wavelengths, where M is also an integer. In general, M is well above N. Each spectrum containing M intensities at the corresponding M wavelengths constitutes an M-dimensional vector in which the M components are these intensities. These vectors are at the heart of key component analysis and are determined by linear algebra, also known in this technique as Singular Value Decomposition (SVD).

As a result of SVD, N eigenvector z where n is a positive integer less than N + 1._nYou get a set of. Eigenvector z_nIs a linear combination of the first N spectra and is often referred to as the major component or major component vector. In general, the major components are orthogonal to each other and are determined as a vector normalized to | Zn | = 1. Main ingredient z_nMay be used to represent the optical signal of a sample with a component of unknown concentration in combination with a normalized key component that has been subjected to appropriate scalar multiplication: x₁z₁+ x₂z₂+ ... + x_nz_nScalar multiplication of positive integers where n is less than N + 1 x_nIs the main component z in a given optical signal_nIt can be judged as the amplitude of. Each multiplier x_nTreats the optical signal as a vector in the M-dimensional wavelength space, and the product of this vector is the main component vector z._nIt is determined by calculating. This is the normalized eigenvector z_nAmplitude of the optical signal in the direction of x_nBring. Amplitude x_nCorresponds to the concentration of N compound.

In a known optical analysis system, the calculation of the direct product of the vector representing the optical signal and the eigenvector representing the main component is performed in the hardware of the optical analysis system using an optical filter. The optical filter has transparency for weighting the optical signal by the components of the eigenvectors representing the main components, i.e. the main component vector constitutes a spectral weighting function. The optical signal that has passed through the filter is detected by a detector that produces a signal with an amplitude proportional to the amplitude of the main component, and therefore a signal with an amplitude proportional to the concentration of the corresponding compound.

In physics, each major component is a "spectrum" composed of forms in the wavelength range of an optical signal. In contrast to the actual spectrum, the major component may have a positive portion within the first spectral range and a negative portion within the second spectral range. In this case, the vector representing this major component has a positive component of the wavelength corresponding to the first spectral range and a negative component of the wavelength corresponding to the second spectral range.<patcit num="1"><text>U.S. Pat. No. 6,198531</text></patcit>

<p> Examples of known optical analysis systems are designed to perform in hardware the calculation of the direct product of the vector representing the optical signal and the eigenvector representing the key component when the key components have positive and negative parts. To. To this end, a portion of the optical signal is directed to a first filter that weights the optical signal by a first spectral weighting function that corresponds to the positive portion of the key component, and is a further portion of the optical signal. Is directed to a second filter that weights the optical signal by a second spectral weighting function that corresponds to the negative part of the major component. The light transmitted by the first and second filters is detected by the first and second detectors, respectively. The signal of the second detector is now subtracted from the signal of the first detector, resulting in a signal of amplitude corresponding to the concentration.</p><p> In other examples, known photoanalytical systems can determine the concentration of the first and second compounds by measuring the amplitude of the corresponding first and second major components. To this end, a portion of the optical signal is directed to a first filter that weights the optical signal by a first spectral weighting function corresponding to the first major component, and a portion of the additional optical signal , Directed to a second filter that weights the optical signal by a second spectral weighting function corresponding to the second major component. The light transmitted by the first and second filters is detected by the first and second detectors, respectively. The signals of the first and second detectors correspond to the amplitudes of the first and second major components, respectively.</p><p> A drawback of known optical analysis systems is the relatively low signal-to-noise ratio.</p><p> An object of the present invention is to provide an optical analysis system capable of providing a signal having a relatively high signal-to-noise ratio with the properties described in the first paragraph.</p><p> The present invention is defined by an independent term. Dependent terms define favorable embodiments.</p>

<p> According to the present invention, the optical analysis system further includes a dispersing element for spectrally dispersing the optical signal, receives the spectrally dispersed optical signal, and is the first spectral weighting function of the optical signal. A distribution element for distributing the first part weighted by the above to the first detector and the second part of the optical signal weighted by the second spectral weighting function to the second detector. The purpose is found in having.</p><p> In a known optical analysis system, the present invention compares signal-to-noise ratios because a significant portion of the optical signal is not detected by any detector and is blocked by, for example, a first or second optical filter. Based on the insight that it is low. As an example, the optical signal received by the first optical filter contains all the information, but the first filter transmits only the portion of the optical signal that corresponds to the first weighting function, therefore. The part of the optical signal corresponding to the second weighting function is blocked by the filter. Light blocked by the first and second optical filters is not detected, resulting in a reduced signal-to-noise ratio.</p><p> According to the present invention, this reduction in signal-to-noise ratio is partially avoided. To that end, optical analysis systems have dispersion elements for spectrally dispersing optical signals, such as grids or prisms. The spectrally dispersed optical signal is received by the distributor, i.e., different parts of the distributor receive different wavelengths of the optical signal. For each wavelength, the partitioning element distributes the first portion of the optical signal weighted by the first spectral weighting function to the first detector and the second spectral weighting function of the optical signal. The second portion weighted by is configured to be distributed to the second detector. Thus, different parts of the optical signal are directed to different detectors, rather than being partially blocked by the first and second optical filters as in known optical analysis systems. As a result, a larger amount of optical signal is detected, resulting in an improved signal-to-noise ratio.</p><p> According to the present invention, the optical signal is not limited to an optical signal having a wavelength visible to the human eye. The optical signal may have spectral elements within the ultraviolet (UV) and / or infrared (IR) spectral range. Therefore, the IR spectral range is near infrared (NIR) and 1TH._zIt may have far infrared rays (FIR) with frequencies above, and also applies to all intermediate wavelengths.</p><p> According to the present invention, the major components are not limited to pure major components. The net main component here refers to the mathematically accurate eigenvectors of a particular compound. The major component may also have a minor contribution from other compounds resulting from imperfections in the determination of the major component. The major component may also correspond to any number of compounds at known concentrations.</p><p> In one embodiment, the main component consists of a positive portion within the first spectral range and a negative portion within the second spectral range, the first portion of the optical signal weighted by the first spectral weighting function. Corresponds to the positive part, the second part of the optical signal weighted by the second spectral weighting function corresponds to the negative part, and the first and second detectors are the first detectors. It is coupled to a signal processor configured to subtract the signal produced by the second detector from the signal produced by. In this embodiment, an optical signal having a major component having a positive part and a negative part can be analyzed with an improved signal-to-noise ratio. In general, the first spectral range is separate from the second spectral range.</p><p> In another embodiment, the major component consists of a first major component and a second major component, and the first portion of the optical signal weighted by the first spectral weighting function corresponds to the first major component. However, the second portion of the optical signal weighted by the second spectral weighting function corresponds to the second major component. This optical analysis system is particularly suitable for analyzing samples with two or more compounds, each containing a corresponding major component. It provides an improved signal-to-noise ratio for the concentrations of two or more compounds.</p><p> In yet another embodiment, the major component has a first major component and a second major component, and the first major component and / or the second major component is positive within the first spectral range. The part has a negative part within the second spectral range.</p><p> It is advantageous if the partitioning element has a surface for receiving a spectrally dispersed optical signal, the surface of which consists of a first set of surface elements and a second set of surface elements, the first set. The surface element of is configured to distribute the spectrally dispersed optical signal to the first detector, and the second set of surface elements is configured to distribute the spectrally dispersed optical signal to the second detector. Will be done. In this embodiment, each surface element receives a certain portion of a spectrally dispersed optical signal based on its position and surface area. The first weighting function is here determined by the position and surface area of the first set of surface elements, and the second weighting function is also determined by the position and surface area of the second set of surface elements. The spectrally dispersed optical signal received by the surface may be reflected and / or diffracted by the surface. Alternatively, it may be transmitted or refracted and / or diffracted.</p><p> The advantage of this embodiment is that the distribution element can be manufactured relatively easily, and a transparent substrate such as a glass substrate provided with an etched and / or polished surface element can be used. Alternatively, the substrate can also be manufactured using a properly molded mold. A further advantage of transparent substrates is the relatively low loss of optical signals.</p><p> In another embodiment, the distribution element comprises an array of liquid crystal cells configured to form a first set of sub-arrays with a refractive index gradient and a second set of sub-arrays with a refractive index gradient. A set of sub-arrays is configured to distribute the spectrally dispersed optical signal to the first detector, and a second set of sub-arrays is configured to distribute the spectrally dispersed optical signal to the second detector. To.</p><p> The index of refraction of the cell is controlled by applying a voltage to the cell of the liquid crystal array. Sub-arrays of cells with a sloped index of refraction are created by applying different voltages to adjacent cells. The tilt can be adjusted by adjusting the voltage. The spectrally dispersed optical signal is refracted by the slope of the index of refraction of the subarray. The first set of sub-arrays refracts the optical signal to the first detector, and the second set of sub-arrays refracts the optical signal to the second detector. In this embodiment, as in the above embodiment, each subarray receives a certain spectral portion of the spectrally dispersed optical signal based on its position. The first weighting function is then determined by the position and surface area of the first set of subarrays, and the second weighting function is determined by the position and surface area of the second set of subarrays.</p><p> The advantage of this embodiment is that the first and second spectral weighting functions can be adjusted relatively easily by adjusting the voltage applied to the cells of the liquid crystal array. This is particularly useful because the same distribution element can be used to analyze optical signals with different key components.</p><p> If the dispersing element disperses the optical signal in the dispersion plane, the optical analysis system further has a focusing member for focusing the dispersed light, and the focusing member has the first focal length and the first focal length in the dispersion plane. It is useful when it has a second focal length in a plane perpendicular to the dispersion plane and the first focal length is different from the second focal length. In this embodiment, the spectrally dispersed optical signals are focused on the distribution element so that different spectral components of the optical signal are received by different parts of the distribution element. This makes it possible to selectively distribute different wavelengths to different detectors. It is useful if the focusing member is configured to focus the optical signals dispersed in the dispersion plane to the distribution element.</p><p> In this embodiment, it would also be beneficial if the optical analysis system had an additional focusing member that focused the first portion of the optical signal on the first detector. This allows the use of a first detector with a relatively small detection area for efficiently detecting the first part.</p><p> For efficient detection when using a detector with a smaller detection area, the optical analysis system will spectrally re-spectrum before the first part of the optical signal is focused on the first detector. It would be beneficial to have additional dispersive elements for focusing. The first part of the optical signal distributed by the distributor is, in principle, still spectrally dispersed, thus limiting the possibility of focusing the first part on a small detection area. By using additional dispersive elements, the first part of the optical signal is spectrally refocused, allowing it to be focused in a smaller region. Therefore, a smaller first detector provided at this focal point can be used. Alternatively, a pinhole or aperture may be placed at this focal point to carry out the confocal detection method.</p>

The aforementioned and other aspects of the optical analysis system, spectroscopic analysis system and blood analysis system according to the present invention will be further described with reference to the drawings.

The drawings are not drawn in actual proportions. In general, matching components are represented by similar symbols.

The optical analysis system 1 that determines the amplitude of the major components of an optical signal is shown in FIGS. 1A and 1B and has a dispersing element 2 for spectrally dispersing the optical signal. The dispersion element 2 is a diffraction grating that spectrally disperses an optical signal in a dispersion plane. The beam path in the dispersion plane is shown in FIG. 1A, and the beam path in the plane perpendicular to the dispersion plane is shown in FIG. 1B. Instead of the diffraction grating, another dispersion element such as a prism may be used.

The optical analysis system further includes a focusing member 3 for focusing the dispersed optical signals. The focusing member 3 has a first focal length in the dispersion plane of FIG. 1A and a second focal length in a plane perpendicular to the dispersion plane shown in FIG. 1B. In this embodiment, the focusing member 3 is a cylindrical lens and focuses the dispersed optical signal in the dispersion plane, but does not focus on the plane perpendicular to the dispersion plane. First focal length F₁Is an infinite second focal length F₂Is different. In an alternative embodiment, the focusing member 3 is an aspherical lens with two finite focal lengths F.₁And F₂May have. As yet another embodiment, the focusing member can be an aspherical mirror.

The focusing member 3 is configured to focus the dispersed optical signals in the dispersion plane on the distribution element 4. In the dispersion plane, light rays of different wavelengths are focused on different parts of the distribution element 4. In FIGS. 1A and 1B, two different wavelength rays are shown, for example, by a dotted line and a chain double-dashed line, respectively.

The distribution element 4 receives the spectrally dispersed optical signal, distributes the first portion of the optical signal weighted by the first spectral weighting function to the first detector 5, and among the optical signals, The second portion weighted by the second spectral weighting function is distributed to the second detector 6. Examples of the distribution element 4 are shown in FIGS. 3 and 4 and will be described below. The first detector 5 and the second detector 6 may be of any type suitable for detecting light. The type includes, for example, two separate photodiodes or split detectors.

In the examples shown in FIGS. 1A and 1B, the optical signal consists of a major component having a positive portion within the first spectral range and a negative portion within the second spectral range. Wavelength λ in the first spectral range₁Certain rays of light and wavelength λ in the second spectral range₂A particular ray of light is indicated by a dotted line and an alternate long and short dash line, respectively. The first portion of the optical signal weighted by the first spectral weighting function corresponds to the positive portion and is detected by the first detector 5. The second portion of the optical signal weighted by the second spectral weighting function corresponds to the negative portion and is detected by the second detector 6. The first detector 5 and the second detector 6 are on a signal processor 7 configured to subtract the signal generated by the second detector 6 from the signal generated by the first detector 5. Be combined.

In another embodiment, the major component has a first major component and a second major component, and the first portion of the optical signal weighted by the first spectral weighting function is the first major component. The second part of the optical signal, weighted by the second spectral weighting function, corresponds to the component, while the second part corresponds to the second major component. The optical analysis system shown in FIGS. 1A and 1B can be used when the first spectral weighting function and the second spectral weighting function do not overlap. However, when the first and second spectral weighting functions overlap at least partially, certain wavelengths are partially detected by the first detector 5 and by the second detector 6. Must also be partially detected. The beam path in the dispersion plane may be similar to that shown in FIG. 1A in this embodiment. The beam path in the plane perpendicular to the dispersion plane is shown in FIG. The wavelengths depicted by the dotted lines are partially detected by the first detector 5 and the second detector 6. The same is true for the wavelengths depicted by the alternate long and short dash line. For all wavelengths, the relative quantities detected by the two detectors 5 and 6 are determined by the two spectral weighting functions. As described below, the distribution element 4 is designed to distribute the optical signal to the two detectors 5 and 6 accordingly.

In the embodiment shown in FIG. 3, the distribution element 4 is a transparent glass substrate having a surface 10 for receiving a spectrally dispersed optical signal. The surface 10 has a first set of surface elements 11 and a second set of surface elements 12. The first set of surface elements 11 is configured to distribute a spectrally dispersed optical signal to the first detector 5, the corresponding light rays being indicated by dotted lines. The second set of surface elements 12 is arranged to distribute the spectrally dispersed optical signal to the second detector 6, and the corresponding light beam is indicated by a chain double-dashed line. In the embodiment of FIG. 3, the first set of surface elements 11 are substantially parallel to each other and are tilted when viewed from the second set of surface elements 12 which are substantially and also parallel to each other. This is advantageous when the distribution element 4 is substantially located on the focal plane of the focal member 3. However, it is not essential according to the present invention. In an alternative embodiment not shown herein, the distribution element has a concave and / or convex surface and the surface element is integrated. In this embodiment, the distribution element may be integrated into the focus member 3 or a further focus member 8.

In FIG. 3, the distribution element 4 is shown in a cross-sectional view of a plane parallel to the dispersion plane. The part of the distribution element 4, which is enlarged and shown in the upper right part of FIG. 3, receives the first wavelength range of the optical signal. Since the first set of surface elements 11 and the second set of surface elements 12 have the same surface area in the projection perpendicular to the propagation direction of the spectrally dispersed optical signals, the light in the first wavelength range 50% of the signal is distributed to the first detector 5 and the other 50% is distributed to the second detector 6.

A part of the distribution element 4, which is enlarged in the lower right part of FIG. 3, receives a second wavelength range of the optical signal. Due to the surface area of surface elements 11 and 12 in a projection perpendicular to the propagation direction of the spectrally dispersed optical signal, 50% of the optical signal in the second wavelength range is sent to the first detector 5. 25% is distributed to the second detector 6, respectively. The surface 10 of the partitioning element 4 further comprises a third set of surface elements 13 which transfers 25% of the optical signal of the wavelength of the second spectral element to a third detector or a beam dump into which it is absorbed. You may point it. In this embodiment, the surface elements 13 are parallel to each other, but instead have any other orientation unless the optical signal is distributed to the first detector 5 or the second detector 6. May be good. The surface element 13 is in some cases useful for satisfying the normalization state of the key component vector. In this embodiment, the first spectral weighting function and the second spectral weighting function are determined by the positions and surface areas of the surface element 11 and the surface element 12.

In another embodiment not shown in the drawings, the distribution element 4 is similar to that shown in FIG. 3, although the spectrally dispersed optical signal is not refracted as in FIG. , Reflected.

The glass substrate shown in FIG. 3 produces a spectrally dispersed optical signal because the optical thickness d, that is, d = tn obtained by multiplying the refractive index n by the geometric thickness t, is a function of position. It is an optical element that refracts. A substantially similar form of this optical thickness d can also be obtained in the alternative embodiment shown in FIG. Instead of a glass substrate, the distribution element 4 has an array 20 of liquid crystal elements configured to provide a morphology substantially similar to the refractive index n. To achieve this goal, a first set of sub-arrays 21 with substantially parallel refractive index slopes and a second set of sub-arrays 22 with substantially parallel refractive index slopes are formed. The slope of the refractive index of the first set is tilted when viewed from the slope of the refractive index of the second set. Similar to a distribution element having a surface 10 with surface elements 11 and 12, it is not essential that the slopes of the refractive index be parallel to each other. The refractive index n of each column C is controlled by applying a voltage V to the cell of the column, as shown in the upper right surface of FIG. The first set of subarrays 21 is configured to distribute the spectrally dispersed optical signals to the first detector 5, the corresponding rays being depicted by dotted lines. The second set of subarrays 22 is configured to distribute the spectrally dispersed optical signal to the second detector 6, the corresponding light rays being depicted by the alternate long and short dash line. In this example, the positions and surface areas of the first and second sets of subarrays 21 and 22 determine the first spectral weighting function and the second spectral weighting function, respectively.

In the embodiments shown in FIGS. 1A, 1B and 2, the optical analysis system 1 further has an additional focal member 8 for focusing the first portion of the optical signal on the first detector 5. In the embodiments shown in FIGS. 1A, 1B and 2, an additional focal member 8 is a lens. Alternatively, or in addition, a focal mirror can be used.

In the embodiments shown in FIGS. 5A and 5B, the optical analysis system 1 further has an additional dispersion element 9 that spectrally recombines the first portion of the optical signal before focusing on the first detector 5. .. In this embodiment, the optical signal enters the optical analysis system 1 from the point light source 14, which may be, for example, a pinhole in the confocal detection method. The optical analysis system 1 has a lens 15 that parallelizes the optical signals, and like the optical analysis systems 1 shown in FIGS. 1A, 1B, and 2, the dispersal element 2 that is a diffraction grating and the focal point that is a cylindrical lens. It has a member 3. The focusing member 3 is configured to focus the dispersed optical signals on the distribution element 4. In this embodiment, the distribution element 4 shown in FIG. 3 is configured to reflect the dispersed optical signal for reparallelization and return it to the focusing member 3. The reparallelized optical signal is still spectrally dispersed there, limiting the possibility of focusing on relatively small spot sizes. In order to spatially recombine the optical signal, the optical signal is sent to a further dispersion element 9, but in this embodiment the dispersion element 9 is a dispersion element 2, that is, the dispersion element 2 and the further dispersion element 9 are It is integrated into one diffraction grating. The light signal weighted by the first weighting function and spectrally recombined and the light signal weighted by the second weighting function and spectrally recombined are the first detector 5 and by the lens 15. Focused on the second detector 6.

In other embodiments not shown in the drawings, the partitioning element 4 transmits and refracts a spectrally dispersed optical signal, and the further dispersing element 9 is a light weighted by a first spectral weighting function. The signal is configured to spectrally recombine before focusing on the first detector 5.

The blood analysis system 40 shown in FIG. 6 has a spectroscopic analysis system 30. The spectroscopic analysis system 30 has a light source 31 for irradiating the sample 32. The light source 31 may be, for example, a light emitting diode, a lamp or a laser. In this example, sample 32 is one blood vessel in one finger of the hand. Blood vessels are illuminated by diodes to produce an optical signal with a major component of amplitude. This optical signal may be, for example, a Raman signal having distinct elements indicating a distinct blood compound such as glucose, lactate, cholesterol, oxygenated hemoglobin and / or dexoxyhemoglobin. Each compound has a corresponding major component. To analyze the concentrations of these compounds, the spectroscopic analysis system 30 has an optical analysis system 1 for determining the amplitude of the major components of the optical signal, as described above.

To determine the concentration of the compound, the signals generated by the first detector 5 and the second detector 6 are further processed by the signal processor 41 of the blood analysis system 40. The signal processor 41 has a memory containing the amplitude of the main component and the concentration of the corresponding compound. The concentration obtained from the amplitude of the main component is displayed by the display element 42.

In summary, the optical analysis system 1 is configured to determine the amplitude of the major components of the optical signal. The optical analysis system 1 includes a first detector 5 that detects an optical signal weighted by a first spectral weighting function and a second detector 6 that detects an optical signal weighted by a second spectral weighting function. Have. Due to the improved signal-to-noise ratio, the optical analysis system 1 also receives the dispersion element 2 that spectrally disperses the optical signal and the spectrally dispersed optical signal, and is the first of the optical signals. A distribution element that distributes the first part weighted by the spectral weighting function to the first detector 5 and the second part of the optical signal weighted by the second spectral weighting function to the second detector 6. Has 4. The spectroscopic analysis system 30 and the blood analysis system 40 each have an optical analysis system 1 according to the present invention.

The above embodiments illustrate, rather than limit, the invention, allowing one of ordinary skill in the art to design many alternative embodiments without departing from the scope of the appended claims. Is written here. In the claims, any code in parentheses should not be construed as limiting the claims. The word "have" does not exclude other elements or steps other than those claimed. The word element does not preclude the existence of the plural form of the element.

<figref num="1A">FIG. 1A is a schematic diagram of the beam path in the dispersion plane of one embodiment of the optical analysis system.</figref><figref num="1B">FIG. 1B is a schematic diagram of the beam path in a plane perpendicular to the dispersion plane of one embodiment of the optical analysis system.</figref><figref num="2">FIG. 2 is a schematic diagram of the beam path in a plane perpendicular to the dispersion plane of another embodiment of the optical analysis system.</figref><figref num="3">FIG. 3 is a cross-sectional view of an embodiment of the distribution element.</figref><figref num="4">FIG. 4 is a cross-sectional view of another embodiment of the distribution element.</figref><figref num="5A">FIG. 5A is a schematic diagram of the beam path in the dispersion plane of another embodiment of the optical analysis system.</figref><figref num="5B">FIG. 5B is a schematic diagram of the beam path in a plane perpendicular to the dispersion plane of another embodiment of the optical analysis system. The beam path in the plane perpendicular to the dispersion plane is widened for simplicity.</figref><figref num="6">FIG. 6 is a schematic diagram of a blood analysis system having a spectroscopic analysis system including an optical analysis system.</figref>