CN117836609A

CN117836609A - Optical fluid analyzer

Info

Publication number: CN117836609A
Application number: CN202280042189.3A
Authority: CN
Inventors: M·安瓦尔; M·H·埃尔·哈龙; Y·M·萨布里; M·萨克
Original assignee: SI-WARE SYSTEMS
Current assignee: SI-WARE SYSTEMS
Priority date: 2021-06-14
Filing date: 2022-06-14
Publication date: 2024-04-05

Abstract

Aspects relate to an optical fluid analyzer that includes a fluid cell configured to receive a sample fluid. The optical fluid analyzer further includes an optical element configured to seal the fluid cell on an opposite side of the fluid cell and allow input light from the light source to be sent through the fluid cell and allow output light from the fluid cell to be input to the spectrometer. The optical fluid analyzer also includes a Machine Learning (ML) engine, such as an Artificial Intelligence (AI) engine, configured to generate a result defining at least one parameter of the fluid based on the spectrum generated by the spectrometer.

Description

Optical fluid analyzer

Cross Reference to Related Applications

The present application claims priority and benefit from non-provisional application number 17/839, 102 filed by the U.S. patent and trademark office at 13, 2022, and provisional application number 63/210, 450 filed by the U.S. patent and trademark office at 14, 2021, 6, the disclosures of which are incorporated herein by reference in their entireties for all applicable purposes as set forth below.

Technical Field

The technology discussed below relates generally to spectroscopy, and more particularly to the mechanism of a spectrooptical fluid analyzer.

Background

The fluid cell may be filled with a fluid, such as a liquid, a gas, or a plasma. The fluid inside the gas cell may be detected by sending light through the fluid cell. A portion of the light is absorbed by the fluid and the remainder of the light can be detected, for example, by a spectrometer. Miniaturization of fluid analyzers can be achieved using microelectromechanical systems (MEMS) spectrometers, such as Fourier Transform Infrared (FTIR) spectrometers. Furthermore, miniaturization of the fluid analyzer may allow for integration of the fluid analyzer with sensors and other components, and enables mass production of integrated devices for fluid analysis.

Disclosure of Invention

The following presents a simplified summary of one or more aspects of the disclosure in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated features of the disclosure, and is intended to neither identify key or critical elements of all aspects of the disclosure nor delineate the scope of any or all aspects of the disclosure. Its sole purpose is to present some concepts of one or more aspects of the disclosure in a form as a prelude to the more detailed description that is presented later.

Aspects of the present disclosure relate to an optical fluid analyzer that includes a fluid cell configured to receive a sample under test (e.g., a fluid such as a liquid, gas, or plasma). The input light is transmitted through the fluid cell, wherein a portion of the light is absorbed by the fluid and the remaining portion of the light can be detected by the spectrometer. In some examples, the spectrometer may be implemented as a microelectromechanical system (MEMS) spectrometer. The optical element is used to seal the fluid cell on opposite sides of the fluid cell and allow light to enter and leave the fluid cell. Furthermore, the optical element allows the spectrum to pass through with negligible absorption values.

The optical fluid analyzer also includes a Machine Learning (ML) engine, such as an Artificial Intelligence (AI) engine, configured to generate a result defining at least one parameter of the fluid based on the spectrum generated by the spectrometer. For example, the AI engine may be configured to predict the measured fluid and its concentration. Other parameters, such as energy content in the fluid, total volatile organic compounds, amount of particulate matter in the fluid, and other suitable parameters may be estimated by the AI engine. In some examples, the AI engine may use correction and prediction models such as chemometrics, kalman filtering, and the like to predict or estimate the parameters.

In some examples, the optical fluid analyzer may be implemented as a in-box spectroscopy laboratory for biological sample detection (such as for viral infection detection). The optical fluid analyzer may be suitable for large-scale screening, for example in the case of epidemics, enabling ultra-fast and low-cost analysis for non-professional users. The optical fluid analyzer may also be scalable and may be mass produced. The fluidic units in the optical fluidic analyzer are designed and implemented such that the fluidic seal remains for infection control purposes.

In one example, an optical fluid analyzer is disclosed. The optical fluid analyzer includes: a light source configured to generate input light, a fluid unit configured to receive a fluid, a first optical window configured to seal the fluid unit on a first side of the fluid unit, and a second optical element configured to seal the fluid unit on a second side of the fluid unit. The first optical element is further configured to direct input light onto a first side of the fluid cell, and the second optical element is further configured to receive output light from the fluid cell via a second side of the fluid cell. The optical fluid analyzer further includes a spectrometer configured to receive the output light via the second optical element and obtain a spectrum of the fluid based on the output light, and a machine learning engine configured to receive the spectrum and generate a result defining at least one parameter of the fluid.

These and other aspects of the invention will be more fully understood upon reading the following detailed description. Other aspects, features and embodiments of the present invention will become apparent to those skilled in the art upon review of the following description of specific exemplary embodiments of the invention in conjunction with the accompanying drawings. While features of the invention may be discussed with respect to certain embodiments and figures below, all embodiments of the invention may include one or more of the advantageous features discussed herein. In other words, while one or more embodiments may be discussed as having certain advantageous features, one or more of these features may also be used in accordance with the different embodiments of the invention discussed herein. In a similar manner, while exemplary embodiments may be discussed below as device, system, or method embodiments, it should be understood that such exemplary embodiments may be implemented in a variety of devices, systems, and methods.

Drawings

Fig. 1 is a diagram illustrating an optical fluid analyzer according to some aspects.

Fig. 2 is a diagram illustrating an exploded view of one example of an optical fluid analyzer, according to some aspects.

Fig. 3A and 3B are diagrams illustrating an optical fluid analyzer including a ball seat sealing system, according to some aspects.

Fig. 4A-4D are diagrams illustrating one example of an optical fluid analyzer including a package glazing sealing system, according to some aspects.

Fig. 5A and 5B are diagrams illustrating examples of ball lens configurations according to some aspects.

Fig. 6A and 6B are diagrams illustrating examples of collimated light coupling designs in accordance with some aspects.

FIG. 7 is a diagram illustrating another example of a collimated light coupling design in accordance with some aspects.

FIG. 8 is a diagram illustrating another example of a collimated light coupling design in accordance with some aspects.

FIG. 9 is a diagram illustrating another example of a collimated light coupling design in accordance with some aspects.

10A and 10B are diagrams illustrating example optical coupling designs for calibrating an optical fluid analyzer, according to some aspects.

Fig. 11A and 11B illustrate exemplary modes of operation of a coated ball lens according to some aspects.

Fig. 12 is a diagram illustrating an exemplary mode switching operation according to some aspects.

Fig. 13 is a flow chart illustrating an exemplary process for calibrating an optical fluid analyzer including a coated ball lens, according to some aspects.

Fig. 14A-14C are diagrams illustrating optical coupling designs with variable optical path lengths, according to some aspects.

Fig. 15 is a diagram illustrating one example of a fluid cell design in accordance with some aspects.

Fig. 16 is a diagram illustrating one example of an optical fluid analyzer integrated with other sensors, according to some aspects.

Fig. 17 is a diagram illustrating another example of an optical fluid analyzer according to some aspects.

Fig. 18 is a diagram illustrating another example of an optical fluid analyzer according to some aspects.

Fig. 19 is a diagram illustrating an example of an optical fluid analyzer configured for virus detection, according to some aspects.

Detailed Description

The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of the various concepts. It will be apparent, however, to one skilled in the art that the concepts may be practiced without these specific details. In some instances, well-known structures and components are shown in block diagram form in order to avoid obscuring the concepts.

Fig. 1 is a diagram illustrating an optical fluid analyzer 100 according to some aspects. In some examples, the optical fluid analyzer 100 may be a portable handheld device. The optical fluid analyzer 100 includes a fluid cell 102. A fluid 108 (e.g., a gas, liquid, or plasma) may enter the fluid cell 102 via one or more fluid inlets 104. Further, the fluid 108 may exit the fluid unit 102 via one or more fluid outlets 106. The fluid 108 within the fluid cell 102 may be detected by directing input light 112 from the light source 110 into the fluid cell 102 via the first optical element 114. The first optical element 114 may be configured to seal the fluid cell 102 on the first side 115a of the fluid cell 102 and to direct the input light 112 into the fluid cell 102 on the first side 115a of the fluid cell 102.

A portion of the input light 112 may be absorbed by the fluid, while the remaining light may be output from the fluid cell 102 as output light 118 via the second optical element 116. The second optical element 116 may be configured to seal the fluid cell 102 on the second side 115b of the fluid cell 102 and direct the output light 118 from the fluid cell 102 to the spectrometer 120. In some examples, the first optical element 114 and the second optical elements 116 may be flat optical windows, such as sapphire windows. In other examples, the first optical element 114 and/or the second optical element 116 may include one or more optical coupling elements, such as a ball lens, a hemispherical lens, or a plano-convex lens. In some examples, optical fluid analyzer 100 may include optical coupling elements in addition to optical elements 114 and 116. For example, optical fluid analyzer 100 may include one or more reflectors (e.g., mirrors), lenses, or other suitable optical coupling elements.

In some examples, the fluid cell 102 has an optimal cell length that balances the light absorption of the fluid 108 and the saturation of the absorption signal. For example, increasing the fluid cell length may increase the light absorption of the fluid 108. As light absorption increases, low fluid concentrations are more readily detected. However, if the fluid cell length is too long, the absorption signal may saturate for fluids 108 having a relatively high concentration.

The spectrometer 120 may be, for example, a Fourier Transform Infrared (FTIR) spectrometer configured to generate an interference pattern that is detectable by a detector of the spectrometer 120 (e.g., an InGaAs photodetector). The output of the detector may then be processed by a spectrometer 120 to obtain a spectrum 122 of the detected light. In some examples, the spectrometer 120 can include a michelson interferometer or a fabry-perot interferometer.

In some examples, the spectrometer 120 may be implemented as, for example, a microelectromechanical system (MEMS) spectrometer, such as a MEMS FTIR spectrometer. As used herein, the term MEMS refers to the integration of mechanical elements, sensors, actuators, and electronics on a common substrate through micro-fabrication techniques. For example, microelectronics are typically fabricated using Integrated Circuit (IC) processes, while micromechanical components are fabricated using compatible micromachining processes that selectively etch away portions of a silicon wafer or add new structural layers to form mechanical and electromechanical components. One example of a MEMS element is a micro-optical component having a dielectric or metallized surface that operates in either a reflective or refractive mode. Other examples of MEMS elements include actuators, detector grooves, and fiber grooves. In some examples, the MEMS spectrometer may include one or more micro-optical components (e.g., one or more reflectors or mirrors) that may be movably controlled by a MEMS actuator. For example, MEMS spectrometers can be fabricated using Deep Reactive Ion Etching (DRIE) processes on silicon-on-insulator (SOI) substrates to fabricate micro-optical components and other MEMS elements capable of processing free-space beams propagating parallel to the SOI substrate.

The spectrum 122 may be input to a Machine Learning (ML) engine 124, such as an AI engine, to generate a result 128 defining at least one parameter of the fluid 108. For example, the results 128 may identify the fluid or obtain other parameters associated with the fluid, such as a concentration of the fluid, an energy content in the fluid, total volatile organic compounds, an amount of particulate matter in the fluid, particulates suspended in the fluid, or other suitable parameters. In some examples, ML engine 124 may use correction and prediction models such as chemometrics, kalman filtering, etc. to predict or estimate the parameter(s). In some examples, ML engine 124 may access an optional database 126 containing fluid data to generate results 128. For example, the fluid data stored on database 126 may be used to train ML engine 124. In one example, the fluid data may contain spectral parameters for known fluids and fluid concentrations. In some examples, the optical fluid analyzer 100 may include a memory having a database 126 stored thereon.

FIG. 2 is a diagram illustrating an exploded view of one example of an optical fluid analyzer 200 according to some aspects. The optical fluid analyzer 200 includes a fluid cell 202 (gas cell), a spectrometer 210, a light source 218, and a light source holder 220 configured to hold the light source 218 in place. The gas unit 202 comprises three main parts: top 204, middle 206, and bottom 208. The top 204 is responsible for maintaining optical alignment between the light source 218 and the fluid cell 202 and includes an opening configured to receive a first optical window (glazing) 212. The middle portion 206 is the main portion of the fluid cell 202 configured to receive a fluid. For example, the middle portion 206 may be coupled to a fluid inlet to receive fluid and to a fluid outlet to flow fluid out of the fluid cell 202. For fluid cell I/O (between the fluid inlet/outlet and the fluid cell), a sealed quick connector may be used to seal the flow of fluid and facilitate the installation of the air tube. The middle portion 206 may also be coupled to one or more light coupling elements 216, the light coupling elements 216 configured to direct input light from a light source 218 into the fluid cell. In the example shown in fig. 2, the optical coupling element(s) include a ball lens 216 coupled between the first optical window 212 and the fluid cell 202.

The bottom 208 of the fluid cell 202 is responsible for maintaining optical alignment between the spectrometer 210 and the rest. The bottom 208 includes walls surrounding the spectrometer 210 to provide physical alignment of the spectrometer 210 with the rest of the fluid cell 202. The bottom 208 also includes an opening configured to receive a second optical window (glazing) 214. The first optical window 212 and the second optical window 214 are also configured to seal the fluid cell 202 from the top and bottom sides. In some examples, the first optical window 212 and the second optical window 214 may be flat optical windows, such as sapphire glass windows. The flat optical windows 212 and 214 are configured to allow transmission of the infrared spectrum with very small absorption values. In some examples, the fluid cell units 204, 206, and 208 may be nickel plated to prevent corrosion due to some fluids.

When a ball lens is used in a sealed optical device, as shown in fig. 2, a ball lens 216 is inserted between the two flat optical windows 212 and 214. The two flat optical windows 212 and 214 may use O-rings (not specifically shown in fig. 2) to seal the fluid cell 202. In accordance with the O-ring design guidelines, an O-ring cannot be used directly with ball lens 216 in examples where ball lens 216 is in contact with a flat surface (e.g., flat optical windows 212 and 214) to maintain uniform pressure over the surface contact area. Thus, in some examples, a ball seat may be used in place of an O-ring to seal the fluid cell 202. The ball seat may replace not only the O-ring, but also the entire sealing system including the flat optical window 212.

Fig. 3A and 3B are diagrams illustrating an optical fluid analyzer 300 including a ball seat sealing system, according to some aspects. Optical fluid analyzer 300 includes a ball lens 302 surrounded by ball seats 304 and 306. The inner surface curvatures of ball seats 304 and 306 are configured to match the lens surface curvatures of ball lens 302 to increase surface contact, thereby increasing sealing efficiency. In some examples, tees 304 and 306 may be formed of rubber.

The optical fluid analyzer 300 further includes a fluid cell (gas cell) 308, an optical window 310, a spectrometer 312, a fluid inlet 316, a fluid outlet 318, and a light source 320. The O-ring 314 is configured to seal the spectrometer 312. The fluid inlet 316 and the fluid outlet 318 are configured to allow fluid (e.g., liquid, gas, or plasma) to enter and exit the fluid cell 308. Ball lens 302 and ball lens mounts 304 and 306 form an optical element configured to seal fluid cell 308 on a first side of fluid cell 308. In addition, ball lens 302 is also configured to direct input light from light source 320 into fluid cell 308. The optical window 310 is configured to seal the fluid cell 308 on a second side of the fluid cell opposite the first side and direct output light from the fluid cell into the spectrometer 312. The fluid cell 308 and the spectrometer 312 may be assembled on a substrate 322, such as a Printed Circuit Board (PCB). In some examples, the ML engine and associated database (e.g., memory) (not shown for simplicity) may be further assembled on the substrate 322. Various sensors, such as pressure sensors, temperature sensors, fluid flow sensors, and other suitable sensors, may be further integrated on the substrate 322.

In the example shown in fig. 3B, the fluid cell 308 is a separate cell from the spectrometer 312 such that each system (optical, electrical, and mechanical) is separate from the others. This can lead to an increase in the overall size and number of components used. Furthermore, by separating the spectrometer 312 and the fluid cell 308 without any seal between the spectrometer 312 and the fluid cell 308, parasitic fluid may penetrate the optical path, resulting in an incorrect reading. Thus, in some examples, a package glazing may replace the fluid cell optical window 310 to be in direct contact with the fluid and spectrometer package.

Fig. 4A-4D are diagrams illustrating one example of an optical fluid analyzer 400 including a package glazing sealing system, according to some aspects. The optical fluid analyzer 400 includes a spectrometer 402 integrated within a package 404, the package 404 being assembled on a substrate 408 (e.g., PCB). The package 404 includes an opening configured to receive a package glazing 406.

The optical fluid analyzer 400 further includes a ball lens 410, ball lens holders 412 and 414 surrounding the ball lens 410, and a fluid cell 416. Ball lens 410 and ball lens seats 412 and 414 form an optical element configured to seal fluid cell 416 on a first side of fluid cell 416. In addition, ball lens 410 is also configured to direct input light from a light source (not shown) into fluid cell 416. The encapsulation glazing 404 is configured to seal the fluidic unit 416 on a second side of the fluidic unit 416 opposite the first side, and direct output light from the fluidic unit 416 into the spectrometer 402. In particular, encapsulation glazing 404 is configured to provide a seal directly between fluid cell 416 and spectrometer 402. An O-ring 418 may be used to maintain a seal between the encapsulation glazing 404 and the fluid cell 416, thereby preventing parasitic leakage of fluid.

In examples where a ball lens is used as the light coupling element to couple input light into the fluidic unit (e.g., as shown in any of fig. 2, 3A, 3B, or 4B), slight misalignment of the lenses may result in a difference in the optical signal and the measured total spectrum. For example, if a housing containing a ball lens is manufactured with a tight gap between the ball lens and the housing, any variation may prevent the top of the housing from being assembled with the lower portion of the housing. This in turn may lead to fluid leakage. Thus, in some examples, rubber shims or springs may be added to fix the position of the ball lens.

Fig. 5A and 5B are diagrams illustrating examples of ball lens configurations according to some aspects. In fig. 5A and 5B, ball lens 502 is positioned in housing 504 and is configured to seal fluid cell 512 on a first side of fluid cell 512. The optical window 506 (e.g., a flat sapphire window) is also configured to seal the fluid cell 512 on a second side of the fluid cell 512 opposite the first side. In fig. 5A, a rubber gasket 508 is shown coupled between the ball lens 502 and the flat optical window 506. In fig. 5B, a spring 510 is shown coupled between the ball lens 502 and the flat optical window 506. Neither the rubber gasket 508 nor the spring 510 blocks fluid flow through the fluid cell 512. Further, each of the rubber washer 508 and the spring 510 creates a pressure on the ball lens 502, which in turn secures the ball lens 502 in place, preventing any change in its position due to movement or vibration of the housing 504.

In the example shown in fig. 3A-5B, the optical coupling element may include a light source and a ball lens that focuses light into the MEMS spectrometer. This design provides simplicity because the ball lens is the only optical component and the ball lens is used for sealing. This design can be used for gases with no difference between the refractive index of the gas and air, for example, so that the gas flow does not affect the focusing and optical coupling of the design. However, liquids or other fluids having significant changes in measured refractive index may affect optical coupling. Thus, in some examples, optical coupling may be performed by a collimation design in which the fluid type does not affect optical coupling.

Fig. 6A and 6B are diagrams illustrating examples of collimated light coupling designs in accordance with some aspects. In the example shown in fig. 6A and 6B, the optical coupling is performed using a collimation setting in which the fluid sample type does not affect the optical coupling. Fig. 6A shows a collimated light coupling design using two ball lenses 602 and 604, while fig. 6B shows a collimated light coupling design using two hemispherical lenses 612 and 614. In each design, two ball lenses 602 and 604 or two hemispherical lenses 612 and 614 couple input light from the light source 608 into the fluid cell 610 on a first side of the fluid cell 610 and receive output light from the fluid cell via a second side of the fluid cell 610 and couple it into the spectrometer 610. Ball lenses 602 and 604 or hemispherical lenses 612 and 614 may not only provide optical coupling, but may also provide sealing of fluid cell 610 (e.g., using ball lens mounts or O-rings, as described above). The two ball lens 602 and 604 design in fig. 6A is less sensitive and more compact in terms of the distance between the infrared light source 608 and the lenses 602 and 604, while the two hemispherical lens 612 and 614 design is easier in terms of sealing the fluid cell 610 (e.g., an O-ring may be used instead of a ball lens holder for sealing).

FIG. 7 is a diagram illustrating another example of a collimated light coupling design in accordance with some aspects. In the example shown in fig. 7, the sphere or hemispherical lens may be replaced by plano-convex lenses 702 and 704. In addition, the collimation arrangement uses a reflector 710 inserted behind the light source 708 to collect the return light of the light source and reflect the return light towards the plano-convex lens 704 for coupling into the fluid cell 706 to nearly double the optical power. In some examples, plano-convex lenses 702 and 704 may be calcium fluoride lenses having focal lengths 716 and 718 of 18mm to accommodate a fluid path length 714 of 50 mm. It should be appreciated that focal lengths 716 and 718 and fluid path length 714 are variable and are not limited to the examples provided herein. In some examples, plano-convex lenses 702 and 704 may provide sealing of fluid cell 706. In other examples, an additional flat optical window may be used to seal the fluid cell 706.

FIG. 8 is a diagram illustrating another example of a collimated light coupling design in accordance with some aspects. In the example shown in fig. 8, the collimation design includes two off-axis parabolic mirrors 802 and 804. The off-axis parabolic mirror 802 is configured to receive input light from the light source 808 and reflect (redirect) the input light into the fluid cell 806 on a first side of the fluid cell 806. Further, the off-axis parabolic mirror 804 is configured to receive the output light from the fluid cell 806 on a second side of the fluid cell 806 and reflect (redirect) the output light into the spectrometer 810. As described above, a flat optical window (not shown) may be used to seal the fluid cell 806.

Off-axis parabolic mirrors 802 and 804 provide metal reflection over a wide spectral range and avoid fresnel light loss from the lens designs shown in fig. 6A, 6B and 7. In addition, the mirrors 802 and 804 may be manufactured by plastic molding that allows for high volume and low cost. In some examples, a single plastic mold including mirrors 802 and 804 may be used to accommodate any sensitivity of alignment in the design shown in fig. 8.

In some examples, the focal length of off-axis parabolic mirror 802 is 15mm and the focal length of off-axis parabolic mirror 804 is 25mm. In this example, the distance 812 between the light source 808 and the off-axis parabolic mirror 802 may be 8.65mm, and the off-axis parabolic mirrors 802 and 804 may each have a width 814 of 12.3mm and a fluid cell length 816 of 100 mm. It should be appreciated that the focal length, distance 812, width 814, and fluid cell length 816 of mirrors 802 and 804 are variable and are not limited to the examples provided herein.

FIG. 9 is a diagram illustrating another example of a collimated light coupling design in accordance with some aspects. In the example shown in fig. 9, the collimating design includes an off-axis parabolic mirror 902 and a lens 904. The off-axis parabolic mirror 902 is configured to receive input light from the light source 908 and reflect (redirect) the input light into the flow cell 906 on a first side of the flow cell 906. Further, the lens 904 is configured to receive the output light from the fluidic unit 906 on a second side of the fluidic unit 906 and reflect (redirect) the output light into the spectrometer 910. In some examples, the lens 904 may be a calcium fluoride lens. The fluidic unit 906 may be sealed using a flat optical window (not shown) or using a combination of flat optical windows adjacent to the off-axis parabolic mirror 902 and the lens 904. In some examples, the lens 904 may be coated to facilitate calibration of the optical fluid analyzer.

In some examples, the focal length of off-axis parabolic mirror 902 is 15mm and the focal length of lens 904 is 18mm. In this example, the distance 912 between the light source 908 and the off-axis parabolic mirror 902 may be 8.65mm, and the off-axis parabolic mirror 902 may have a width 914 of 12.3mm and a fluid cell length 916 of 100 mm. It should be appreciated that the focal length, distance 912, width 914, and fluid cell length 916 of mirrors 902 and 904 are variable and are not limited to the examples provided herein.

10A and 10B are diagrams illustrating example optical coupling designs for calibrating an optical fluid analyzer, according to some aspects. The optical coupling design shown in fig. 10 includes a ball lens 1002, the ball lens 1002 having a filter responsive coating 1004 on opposite ends thereof. The central region of ball lens 1002 is not coated with filter response coating 1004. Coating 1004 absorbs and removes the reference wavelength lambda used for calibration _o All wavelengths except those. The response of the coating 1004 is shown in fig. 10B.

Fig. 11A and 11B illustrate exemplary modes of operation of coated ball lens 1102 according to some aspects. In the first mode, as shown in FIG. 11A, the filter responsive coating 1104 of ball lens 1102 is outside the optical path 1106 of the input light from the light source (not shown). Thus, no absorption of the input light occurs, and the spectrum reflects the absorption of the fluid in the fluid cell (not shown). In the second mode, as shown in FIG. 11B, the optical path 1106 of the input light passes through the filter responsive coating 1104 of the ball lens 1102, and as a result, absorption occurs, producing the spectrum shown in FIG. 10B. Thus, the second mode may be referred to as a calibration mode. For example, in the calibration mode, the wavelength λ may be converted to a wavelength λ using, for example, digital signal processing _o The value of (2) and the referenceThe test design values are compared. Calibration and drift correction may then be performed based on the comparison. For example, the optical fluid analyzer may be configured to calibrate the machine learning engine during a calibration mode.

Fig. 12 is a diagram illustrating an exemplary mode switching operation according to some aspects. In the example shown in fig. 12, ball lens 1202 includes a filter response coating 1204 on opposite ends thereof, as shown in fig. 10A, 11A, and 11B. The rotation device 1206 is coupled to the ball lens 1202 and is configured to rotate the ball lens 1202 between a first orientation (e.g., the first mode shown in fig. 11A) in which input light passes through the ball lens 1202 without passing through the filter response coating 1204, and a second orientation (e.g., the second mode shown in fig. 11B) in which input light passes through the filter response coating 1204 of the ball lens 1202. For example, the rotation device 1206 may include springs and fingers controlled by an optical fluid analyzer to produce a 90 degree rotation of the ball lens 1202 between two modes of operation.

Fig. 13 is a flow chart illustrating an exemplary process for calibrating an optical fluid analyzer including a coated ball lens, according to some aspects. At block 1302, the optical fluid analyzer may enter a calibration mode of the device. At block 1304, the optical fluid analyzer may mechanically rotate the coated ball lens (e.g., using the rotation device shown in fig. 12) 90 degrees to a second orientation shown in fig. 11B such that the filter response coating of the ball lens is within the optical path of the input light from the light source. At block 1306, the optical fluid analyzer may obtain a spectrum when the coated ball lens is in the second orientation. At block 1308, the optical fluid analyzer may compare the spectrum to a reference wavelength. At block 1310, the optical fluid analyzer may obtain a correction factor and a calibration parameter based on the comparison. The correction factors and calibration parameters may then be used to train the machine learning engine. At block 1312, the optical fluid analyzer may mechanically rotate the coated ball lens (e.g., using the rotation device shown in fig. 12) 90 degrees to the first orientation shown in fig. 11A such that the filter response coating of the ball lens is outside the optical path of the input light from the light source to enable the optical fluid analyzer to obtain a spectrum of the fluid sample to be measured.

Fig. 14A-14C are diagrams illustrating one example of an optical coupling design with variable optical path lengths, according to some aspects. The light coupling design includes two optical elements 1402 and 1404 for coupling input light into the fluid cell 1406 on a first side of the fluid cell 1406 and coupling output light from the fluid cell 1406 via a second side of the fluid cell 1406. The optical elements 1402 and 1404 may include, for example, flat optical windows, ball lenses, hemispherical lenses, plano-convex lenses, or other suitable optical coupling elements. To overcome the challenges of parasitic interference effects in the fluid cell 1406 due to multiple reflections of light and micro-scale path lengths 1410 (e.g., 20 μm to 100 μm) in the fluid cell, at least one of the optical elements (e.g., optical element 1402) may be coupled to an actuator 1408 (e.g., micro/actuation mechanism), the actuator 1408 configured to cause movement of the optical element 1402 to follow movement d (t) in the fluid cell 1406 at a nominal value d _o The vicinity continuously changes the optical path length as shown in fig. 14A. The continued movement of the optical element 1402 causes dithering of the optical path length such that the average value of d (t) is zero, as shown by the comparison between fig. 14B (no oscillatory movement) and fig. 14C (oscillatory movement). In other examples, dithering of the optical path length may be achieved by electro-optic effects and/or thermo-optic effects applied to the optical element 1402. For example, an electric field may be applied across the optical element 1402, or a micro-heater may be integrated with the optical element 1402.

Fig. 15 is a diagram illustrating one example of a fluid cell design in accordance with some aspects. The fluidic unit design includes two optical elements 1502 and 1504 configured to seal a fluidic unit 1506 on either side of the fluidic unit. To overcome stiction of the fluid (e.g., oil sample) within the fluid cell 1506, a coating 1508 may be applied on an inner surface (facing the fluid cell 1506) of at least one of the optical elements 1502 and 1504 to repel the fluid (e.g., prevent stiction of the fluid). In some examples, the coating 1508 may be hydrophobic or fully hydrophobic. As a result, the fluid can be easily purged without the need for a consumable cleaning solution. In some examples, coating 1508 may also be applied to inner wall 1510 in fluid cell 1506.

Fig. 16 is a diagram illustrating one example of an optical fluid analyzer 1600 integrated with other sensors, according to some aspects. The optical fluid analyzer 1600 includes a MEMS-based FTIR fluid analyzer 1602 (e.g., including a light source, optical elements, fluidic units, and a spectrometer (interferometer/detector)), an Artificial Intelligence (AI) engine 1604 (e.g., an ML engine), and a database 1606 integrated with one or more other sensors. Examples of sensors include, but are not limited to, pressure sensor 1608, flow (fluid flow) sensor 1610, temperature sensor 1612, and humidity sensor 1614. The sensors 1608-1614 may be synchronized together and controlled via integrated electronics and synchronization signal circuit 1616 to sense the fluid while the MEMS-based FTIR fluid analyzer 1602 obtains a spectrum of the fluid. The output of each sensor 1608-1614 (e.g., sensor data related to the fluid in the fluid cell) may be input to the AI engine 1604 along with the spectrum of the fluid to assist the AI engine 1604 in predicting fluid characteristics and specifications. The AI engine can also be trained with fluid data in database 1606 to produce fluid-related results 1618.

Fig. 17 is a diagram illustrating another example of an optical fluid analyzer 1700 according to some aspects. The optical fluid analyzer 1700 includes a light source 1702, an optical coupling element 1704, a microfluidic cell 1706 configured to receive a fluid under test, and a spectrometer 1708. In the example shown in fig. 17, the microfluidic cell 1706 is placed on a spectrometer 1708. Thus, the microfluidic cell 1706 may be used as a transmissive cell that includes an optical window configured to seal the microfluidic cell 1706 and pass light through the microfluidic cell. Furthermore, a light source 1702 having a compact form factor may be integrated over the microfluidic unit 1706.

Fig. 18 is a diagram illustrating another example of an optical fluid analyzer 1800 according to some aspects. The optical fluid analyzer includes a light source 1802, a light coupling element 1804, a microfluidic cell 1806, and a spectrometer 1808. The spectrometer 1808 may be integrated into the optical package 1810. The microfluidic cell 1806 may also include an optical window configured to seal the microfluidic cell 1806 and pass light through the microfluidic cell 1806. In addition, microfluidic cell 1806 may also be used as a glass encapsulation window for encapsulation 1810. Thus, the microfluidic cell/glass package window may be configured to seal the spectrometer 1808 (e.g., MEMS-based FTIR spectrometer and detector). From an assembly point of view, the microfluidic cell 1806 may be on the same production line as the optical package for better assembly and production processing.

Fig. 19 is a diagram illustrating one example of an optical fluid analyzer 1900 configured for virus detection, in accordance with some aspects. In some examples, optical fluid analyzer 1900 may be configured to measure a spectrum of a patient breath sample and predict a type of viral infection of the patient. For example, using different chemometric techniques, the ML engine (AI engine) of an optical fluid analyzer can predict the virus type from the absorption bands of the spectrum. To measure a breath sample, optical fluid analyzer 1900 may include an input pipe 1902 through which a patient may blow air from their mouth into a fluid cell of optical fluid analyzer 1900.

The following provides an overview of examples of the present disclosure.

Example 1: an optical fluid analyzer, comprising:

a light source configured to generate input light;

a fluid unit configured to receive a fluid;

a first optical element configured to seal the fluid cell on a first side of the fluid cell, the first optical element further configured to direct the input light onto the first side of the fluid cell;

a second optical element configured to seal the fluid cell on a second side of the fluid cell opposite the first side, the second optical element further configured to receive output light from the fluid cell via the second side of the fluid cell;

A spectrometer configured to receive the output light via the second optical element and obtain a spectrum of the fluid based on the output light; and

a machine learning engine configured to receive the spectrum and generate a result defining at least one parameter of the fluid.

Example 2: the optical fluid analyzer of example 1, wherein the second optical element comprises:

a flat optical window positioned between the fluid cell and the spectrometer and configured to seal the fluid cell on the second side of the fluid cell.

Example 3: the optical fluid analyzer of example 2, wherein the first optical element comprises:

an additional flat optical window is positioned between the light source and the fluid cell and is configured to seal the fluid cell on the first side of the fluid cell.

Example 4: the optical fluid analyzer of example 3, further comprising:

a ball lens coupled between the additional flat optical window and the fluid cell.

Example 5: the optical fluid analyzer of example 2, wherein the first optical element comprises a ball lens coupled between the light source and the first side of the fluid cell.

Example 6: the optical fluid analyzer of example 5, further comprising:

a ball seat is configured to provide a seal between the ball lens and the first side of the fluid cell.

Example 7: the optical fluid analyzer of examples 5 or 6, wherein the flat optical window comprises a package glazing of a package, the package comprising the spectrometer, and the optical fluid analyzer further comprising:

an O-ring configured to provide a seal between the encapsulation glazing and the second side of the fluid cell.

Example 8: the optical fluid analyzer of example 2, further comprising:

a ball lens configured to direct the input light onto the first side of the fluidic unit; and

a rubber gasket or spring coupled between the ball lens and the flat optical window.

Example 9: the optical fluid analyzer according to any one of examples 1 to 8, wherein the first optical element and the second optical element comprise an optical coupling element having a collimating design, the optical coupling element comprising:

a first lens configured to couple the input light into the fluid cell on the first side of the fluid cell; and

A second lens configured to receive the output light from the fluidic unit via the second side of the fluidic unit and couple the output light into the spectrometer.

Example 10: the optical fluid analyzer of example 9, wherein each of the first and second lenses comprises a ball lens or a hemispherical lens.

Example 11: the optical fluid analyzer of example 9, wherein each of the first lens and the second lens comprises a plano-convex lens, and further comprising:

a reflector is coupled behind the light source and configured to collect return rays of the input light and reflect the return rays toward the first lens.

Example 12: the optical fluid analyzer according to any one of examples 1 to 3, further comprising:

a first off-axis parabolic mirror configured to receive the input light from the light source and reflect the input light onto the first side of the fluid cell; and

a second off-axis parabolic mirror is configured to receive the output light from the fluid cell via the second side of the fluid cell and reflect the output light into the spectrometer.

Example 13: the optical fluid analyzer according to any one of examples 1 to 3, further comprising:

an off-axis parabolic mirror configured to receive the input light from the light source and reflect the input light into the fluid cell on the first side of the fluid cell, wherein the second optical element comprises a lens configured to receive the output light from the fluid cell via the second side of the fluid cell and direct the output light into the spectrometer.

Example 14: the optical fluid analyzer according to any one of examples 1, 2, or 5-9, wherein the first optical element comprises a ball lens coupled between the light source and the first side of the fluid cell, the ball lens being coated with a filter responsive coating on opposite ends thereof.

Example 15: the optical fluid analyzer of example 14, further comprising:

a rotating device coupled to the ball lens and configured to rotate the ball lens between a first orientation in which the input light passes through the ball lens but not through the filter response coating and a second orientation in which the input light passes through the filter response coating of the ball lens;

Wherein the optical fluid analyzer is configured to operate in a calibration mode to calibrate the machine learning engine when the ball lens is in the second orientation.

Example 16: the optical fluid analyzer according to any one of examples 1 to 15, further comprising:

an actuator coupled to at least one of the first optical element or the second optical element and configured to cause movement of the at least one of the first optical element or the second optical element to change an optical path length in the fluid cell.

Example 17: the optical fluid analyzer according to any one of examples 1 to 16, wherein at least one of the first optical element or the second optical element includes a coating on an inner side thereof facing the fluid unit to prevent stiction of the fluid.

Example 18: the optical fluid analyzer according to any one of examples 1 to 17, further comprising:

a database comprising fluid data configured to train the machine learning engine.

Example 19: the optical fluid analyzer according to any one of examples 1 to 18, further comprising:

At least one sensor configured to generate sensor data related to the fluid in the fluid cell and provide the sensor data to the machine learning engine.

Example 20: the optical fluid analyzer of example 19, wherein said at least one sensor comprises at least one of: pressure sensor, flow sensor, temperature sensor or humidity sensor.

Example 21: the optical fluid analyzer according to any one of examples 1 to 20, wherein the fluid cell comprises a microfluidic cell.

Example 22: the optical fluid analyzer of example 21, wherein the second optical element comprises a package glazing of a package, the package comprising the spectrometer, the package glazing comprising the microfluidic cell.

Example 23: the optical fluid analyzer according to any one of examples 1 to 22, wherein the fluid comprises a patient breath sample, and further comprising:

an input tube is coupled to the fluid unit and configured to receive the patient breath sample and provide the patient breath sample into the fluid unit.

Example 24: the optical fluid analyzer according to any one of examples 1-23, wherein the spectrometer comprises a microelectromechanical system (MEMS) based Fourier Transform Infrared (FTIR) spectrometer.

In this disclosure, the word "exemplary" is used to mean "serving as an example, instance, or illustration. Any embodiment or aspect described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other aspects of the invention. Likewise, the term "aspect" does not require that all aspects of the disclosure include the discussed feature, advantage or mode of operation. The term "coupled," as used herein, refers to a direct or indirect coupling between two objects. For example, if object A physically touches object B, and object B touches object C, then objects A and C may still be considered coupled to each other even though they do not directly physically touch each other. For example, a first object may be coupled to a second object even though the first object is never in direct physical contact with the second object. The terms "circuitry" and "circuitry" are used broadly and are intended to encompass both hardware implementations of electrical devices and conductors, as well as software implementations of information and instructions that, when connected and configured, enable performance of the functions described in this disclosure, not limited to the type of electronic circuitry, which, when executed by a processor, enables performance of the functions described in this disclosure.

One or more of the components, steps, features, and/or functions illustrated in fig. 1-19 may be rearranged and/or combined into a single component, step, feature, or function, or embodied in several components, steps, or functions. Additional elements, components, steps, and/or functions may also be added without departing from the novel features disclosed herein. The apparatus, devices, and/or components shown in fig. 1-19 may be configured to perform one or more of the methods, features, or steps described herein. The novel algorithms described herein may also be implemented effectively in software and/or embedded in hardware.

It should be understood that the specific order or hierarchy of steps in the methods disclosed is an illustration of exemplary processes. Based on design preferences, it is understood that the specific order or hierarchy of steps in the methods may be rearranged. The accompanying method claims present elements of the various steps in a sample order, and are not meant to be limited to the specific order or hierarchy presented, unless specifically recited therein.

The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but is to be accorded the full scope consistent with the language of the claims, wherein reference to an element in the singular is not intended to mean "one and only one" unless specifically so stated, but rather "one or more. The term "some" means one or more unless specifically stated otherwise. The phrase referring to "at least one of" a list of items refers to any combination of those items, including individual members. As an example, "at least one of: "a", "b" or "c" are intended to cover: a, a; b; c, performing operation; a and b; a and c; b and c; and a, b and c. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known to those of ordinary skill in the art or that later become known are expressly incorporated herein by reference and are intended to be encompassed by the claims. Furthermore, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. Any claim element should not be construed as limited by the provision of clause 112 (f) at volume 35 of the united states code unless the element is explicitly recited using the phrase "means for … …" or, in the case of method claims, the phrase "step for … …".

Claims

1. An optical fluid analyzer, comprising:

a light source configured to generate input light;

a fluid unit configured to receive a fluid;

a first optical element configured to seal the fluid cell on a first side of the fluid cell, the first optical element further configured to direct the input light to the fluid cell on the first side of the fluid cell;

2. The optical fluid analyzer of claim 1, wherein the second optical element comprises:

3. The optical fluid analyzer of claim 2, wherein the first optical element comprises:

4. The optical fluid analyzer of claim 3, further comprising:

5. The optical fluid analyzer of claim 2, wherein the first optical element comprises a ball lens coupled between the light source and the first side of the fluid cell.

6. The optical fluid analyzer of claim 5, further comprising:

7. The optical fluid analyzer of claim 5, wherein the flat optical window comprises a package glazing of a package, the package comprising the spectrometer, and the optical fluid analyzer further comprising:

8. The optical fluid analyzer of claim 2, further comprising:

a ball lens configured to direct the input light into the fluid cell on the first side of the fluid cell; and

9. The optical fluid analyzer of claim 1, wherein the first optical element and the second optical element comprise optical coupling elements having a collimating design, the optical coupling elements comprising:

10. The optical fluid analyzer of claim 9, wherein each of the first and second lenses comprises a ball lens or a hemispherical lens.

11. The optical fluid analyzer of claim 9, wherein each of the first and second lenses comprises a plano-convex lens, and further comprising:

12. The optical fluid analyzer of claim 1, further comprising:

a first off-axis parabolic mirror configured to receive the input light from the light source and reflect the input light into the fluid cell on the first side of the fluid cell; and

13. The optical fluid analyzer of claim 1, further comprising:

14. The optical fluid analyzer of claim 1, wherein the first optical element comprises a ball lens coupled between the light source and the first side of the fluid cell, the ball lens coated with a filter responsive coating on opposite ends thereof.

15. The optical fluid analyzer of claim 14, further comprising:

16. The optical fluid analyzer of claim 1, further comprising:

17. The optical fluid analyzer of claim 1, wherein at least one of the first optical element or the second optical element comprises a coating on an inner side thereof facing the fluid cell to prevent stiction of the fluid.

18. The optical fluid analyzer of claim 1, further comprising:

19. The optical fluid analyzer of claim 1, further comprising:

20. The optical fluid analyzer according to claim 19, wherein said at least one sensor comprises at least one of: pressure sensor, flow sensor, temperature sensor or humidity sensor.

21. The optical fluid analyzer of claim 1, wherein the fluidic unit comprises a microfluidic unit.

22. The optical fluid analyzer according to claim 21, wherein said second optical element comprises a package glazing of a package, said package comprising said spectrometer, said package glazing comprising said microfluidic cell.

23. The optical fluid analyzer of claim 1, wherein the fluid comprises a patient breath sample, and further comprising:

24. The optical fluid analyzer according to claim 1 wherein said spectrometer comprises a microelectromechanical system (MEMS) based Fourier Transform Infrared (FTIR) spectrometer.