Patent Application
20230311120
In some aspects of the present description, an optical system for examining an optical characteristic of a test material at at least a first wavelength is provided, the optical system including an elongated hollow structure elongated along a length thereof and having one or more walls extending along the length of the hollow structure and defining an elongated chamber therebetween configured to receive the test material. The elongated hollow structure includes at least a first light opening, such that for the at least the first wavelength, the one or more walls have an optical reflectance of greater than about 50% for incident angles of up to at least 40 degrees, and at least one of the at least the first light opening has an optical transmittance of greater than about 50% for at least one incident angle.
In some aspects of the present description, an optical system for examining an optical characteristic of a test material at at least a first wavelength is provided, the optical system having a main channel extending along a first direction and at least one branch channel extending along a different second direction from a first location of the main channel between longitudinal ends of the main channel. Each of the main and branch channels include an open top, a closed bottom, and one or more walls extending from the closed bottom to the open top. At least about 60% of the open top of the main channel, but no more than about 40% of the open top of each of the branch channels, is covered with a reflective top layer. Each of the reflective top layer and the one or more walls have an optical reflectance of greater than about 50% for incident angles of up to at least 50 degrees at the at least the first wavelength.
In the following description, reference is made to the accompanying drawings that form a part hereof and in which various embodiments are shown by way of illustration. The drawings are not necessarily to scale. It is to be understood that other embodiments are contemplated and may be made without departing from the scope or spirit of the present description. The following detailed description, therefore, is not to be taken in a limiting sense.
Biological assays (bio-assays) utilizing microfluidic channels allow diagnostic tests to be performed with a significantly lower sample volume in a compact form factor. These configurations may also reduce or eliminate the need for sample preparation and washing steps, reducing the overall time required to run assays. Some microfluidic devices incorporate automatic fluidic controls such as flow rate, mixing, etc. using features like valves and switches. However, as the sample volume decreases, the total sample available for light to interact with becomes low, reducing the signal strength. In addition, when the small sample volume is spread across thin microfluidic channels, the thickness of the channels limits the effective pathlength available for light to interact with the sample. This reduces the sensitivity of microfluidic devices in low concentration regimes. Technologies and device architectures that increase the effective pathlength have potential to increase the sensitivity of microfluidic devices.
According to some aspects of the present description, an optical system for examining an optical characteristic of a test material at at least a first wavelength may include an elongated hollow structure. In some embodiments, the elongated hollow structure may be elongated along a length (e.g., along an x-axis) thereof and may include one or more walls extending along the length of the hollow structure and defining an elongated chamber therebetween.
In some embodiments, the one or more walls may include a metal layer extending along the length of the hollow structure. In some embodiments, the metal layer may be exposed to the elongated chamber and configured to come into physical contact, or near physical contact, with the test material. In other embodiments, the metal layer may be embedded in the one or more walls so as not to make physical contact with the test material. For example, in some embodiments, the metal layer may be disposed between two outer layers of a separate material (e.g., a polycarbonate material, or any other appropriate material). In such embodiments, the metal layer may be adhered to the outer layers by an adhesive (e.g., an optically clear adhesive). In some embodiments, the metal layer may include one or more of gold, silver, aluminum, copper, and tin. In some embodiments, at least a portion of the one or more walls may include an optical diffuser exposed to the elongated chamber and configured to scatter light primarily forwardly along the length of the hollow structure.
In some embodiments, the one or more walls may include a multilayer optical film extending along the length of the hollow structure. The multilayer optical film may include a plurality of microlayers numbering at least 4, or at least 5, or at least 8, or at least 10, or at least 20, or at least 50, or at least 100, or at least 150, or at least 200, or at least 250, or at least 300 in total. In some embodiments, each of the microlayers may have an average thickness of less than about 500 nm, or about 450 nm, or about 400 nm, or about 350 nm, or about 300 nm, or about 250 nm, or about 200 nm.
In some embodiments, at least some of the microlayers in the plurality of microlayers may include an inorganic material. In such embodiments, the inorganic material may include one or more of an oxide, a nitride, a carbide, and a metal. In embodiments where the inorganic material includes an oxide, the oxide may be one or more of a metal oxide, silicon oxide, silicon dioxide, zirconium oxide, and titanium oxide. In embodiments where the inorganic material includes a nitride, the nitride may include one or more of silicon nitride, zirconium nitride and titanium nitride. In embodiments where the inorganic material includes a carbide, the carbide may include one or more of silicon carbide and germanium carbide. In embodiments where the inorganic material includes a metal, the metal may include one or more of gold, silver and aluminum. In some embodiments, at least some of the microlayers in the plurality of microlayers may include an organic material. In such embodiments, the organic material may include a polymer.
In some embodiments, the elongated chamber may be configured to receive the test material. In some embodiments, the elongated hollow structure may include at least a first light opening. In some embodiments, the at least the first light opening may be disposed proximate a first end of the one or more walls
In some embodiments, for the at least the first wavelength, the one or more walls may have an optical reflectance of greater than about 50% for incident angles of up to at least 40 degrees. In some embodiments, at least one of the at least the first light opening may have an optical transmittance of greater than about 50%, or greater than about 60%, or greater than about 70%, or greater than about 80%, or greater than about 90%, or greater than about 95% for at least one incident angle.
In some embodiments, the test material may include a liquid test material configured to substantially fill the elongated chamber. In other embodiments, the test material may be a solid test material configured to be disposed along at least 50% of the length of the elongated chamber. In some embodiments, the elongated chamber, as seen from a top view, may be substantially straight along at least 50% of its length. In other embodiments, the elongated chamber, as seen from a top view, may have a serpentine shape along at least 50% of its length.
In some embodiments, the optical system may further include a light source disposed in the elongated hollow structure proximate a second end, opposite the first end, of the one or more walls. In such embodiments, the light source may be configured to emit light having the at least the first wavelength. In some embodiments, the emitted light may be configured to propagate along the elongated hollow structure and exit the elongated hollow structure through the at least the first light opening after going through the test material and being reflected multiple times by the one or more walls. In some embodiments, the optical system may not include any light openings proximate the second end of the one or more walls. In some embodiments, the at least the first light opening include the first light opening disposed proximate a first end of the one or more walls and a different second light opening disposed proximate an opposite second end of the one or more walls. In some embodiments, the at least the first light opening may further include a physical third light opening for delivering the test material to the elongated chamber therethrough.
In some embodiments, for the at least the first wavelength, the first light opening may have an optical transmittance of greater than about 60% for the at least one incident angle and the second light opening may have an optical reflectance of greater than about 60% for at least one incident angle.
In some embodiments, the first light opening may be disposed proximate a first end of the one or more walls, and the hollow structure may further include at least a second opening disposed proximate an opposite second end of the one or more walls. In some embodiments, the second opening may be configured to receive an optical fiber therethrough for injecting light into the elongated chamber. In some embodiments, the first light opening is an optical, but not a physical, light opening. In other embodiments, the first light opening is a physical light opening. In some embodiments, at least one of the at least the first light opening may include a plurality of regularly arranged microstructures for redirecting light.
In some embodiments, the at least one of the one or more walls (e.g., a “bottom” wall) may include a recessed cavity configured to receive and be substantially filled with the test material. In some embodiments, the at least one of the one or more walls may be configured to have the test material coated thereon so that the coated test material faces the elongated chamber.
In some embodiments, at least a portion of the one or more walls may include a porous section facing the elongated chamber. In such embodiments, a second material may substantially fill the pores and is configured to interact with the test material. In some embodiments, the interaction between the test material and the second material may result in a resulting material, wherein same optical characteristics of the test and resulting materials are different from each other by at least 1%, or at least 2%, or at least 5%, or at least 10%, or at least 20%, or at least 30% at the at least the first wavelength. In some such embodiments, the same optical characteristics of the test material and resulting material may be optical absorbances at the at least the first wavelength.
In some embodiments, at least a portion of an innermost surface of the one or more walls facing the elongated chamber may be functionalized with receptors configured to bind with analytes in the test material. In some such embodiments, the receptors may include biological receptors. In such embodiments, the biological receptors may include one or more of enzymes, enzyme inhibitors, antigens, hormones, antibodies, polynucleotide, proteins, steroids, cells, ribozymes and cytokines. In some such embodiments, the analytes may include biological analytes. In such embodiments, the biological analytes may include one or more of enzymes, enzyme inhibitors, antigens, hormones, antibodies, polynucleotide, proteins, steroids, cells, ribozymes and cytokines. In some such embodiments, at least some of the analytes may include, or may be attached to, a fluorescent labeling agent configured to absorb light at the at least the first wavelength and emit light having a different second wavelength. In some embodiments, the receptors may be further configured to bind with second analytes. In such embodiments, at least some of the second analytes may comprise, or may be attached to, a fluorescent labeling agent configured to absorb light at the at least the first wavelength and emit light having a different second wavelength. In some embodiments, the optical system of claim may further include a porous material disposed in the elongated chamber. In such embodiments, the porous material may include pores and receptors bound therein. In such embodiments, the receptors may be configured to bind with analytes in the test material.
In some embodiments, an innermost surface of at least portions of the one or walls facing the elongated chamber may be hydrophilic. In other embodiments, an innermost surface of at least portions of the one or walls facing the elongated chamber may be hydrophobic. As used herein, the term “hydrophilic” refers to a surface that is wet by aqueous solutions and does not express whether or not the material absorbs aqueous solutions. By “wet” it is meant that the surface exhibits spontaneous wicking when contacted with an aqueous fluid. An aqueous fluid comprises 50% or more by volume of water. In some embodiments, a hydrophilic surface exhibits and advancing (maximum) water contact angle of less than 90 degrees, preferably 45 degrees or less. As used herein, the term “hydrophobic” refers to a surface that lacks spontaneous wicking when contact with an aqueous fluid. In some embodiments, a hydrophobic surface exhibits an advancing water contact angle of 70 degrees or greater, preferably 90 degrees or greater.
In some embodiments, the elongated chamber may have a cross-sectional area in a plane orthogonal to the length of the hollow structure, and wherein the cross-sectional area varies by less than about 20%, or less than about 15%, or less than about 10%, or less than about 5% along a majority of the length of the hollow structure. In other embodiments, the elongated chamber may have a cross-sectional area in a plane orthogonal to the length of the hollow structure, and wherein the cross-sectional area varies by greater than about 20%, or greater than about 30%, or greater than about 40%, or greater than about 50% along a majority of the length of the hollow structure. In some embodiments, along a majority of the length of the hollow structure, the elongated chamber may taper from a larger cross-section to a narrower cross-section.
According to some aspects of the present description, an optical system for examining an optical characteristic of a test material at at least a first wavelength may include a main channel extending along a first direction (e.g., along an x-axis of the system) and at least one branch channel extending along a different second direction (e.g., along a y-axis of the system) from a first location of the main channel between longitudinal ends of the main channel. In some embodiments, each of the main and branch channels may have an open top, a closed bottom, and one or more walls extending from the closed bottom to the open top. In some embodiments, at least about 60%, or at least about 65%, or at least about 70%, or at least about 80%, or at least about 85%, or at least about 90% of the open top of the main channel, but no more than about 40%, or about 35%, or about 30%, or about 25%, or about 20%, or about 15%, or about 10%, or about 5% of the open top of each of the branch channels, may be covered with a reflective top layer. In some embodiments, each of the reflective top layer and the one or more walls may have an optical reflectance of greater than about 50% for incident angles of up to at least 50 degrees at the at least the first wavelength.
In some embodiments, the optical system may further include at least one light source disposed proximate one of the longitudinal ends of the main channel. In such embodiments, the at least one light source may be configured to emit light having the at least the first wavelength. In some embodiments, the optical system may further include at least one detector disposed proximate the other one of the longitudinal ends of the main channel. In such embodiments, the at least one detector may be configured to detect the emitted light. In such embodiments, the at least one detector include one or an array including one or more of a charged coupled device (CCD), a charge injection device (CID), a photodiode, an organic photodiode (OPD), a complementary metal-oxide-semiconductor (CMOS), and a thin-film transistor (TFT). In some embodiments, the test material may be configured to change an optical intensity of the emitted light, and at least one of the detectors in the at least one detector may be configured to detect the change in the optical intensity of the emitted light.
Turning now to the figures,
In some embodiments, the elongated hollow structure 20 may further include at least a first light opening. In some embodiments, the at least the first light opening may include a first light opening 60 disposed proximate a first end 34a, 42a of the one or more walls 30, 40 and a different second light opening 61 disposed proximate an opposite second end 34b, 42b of the one or more walls 30, 40. In some embodiments, the at least the first light opening may further include a physical third light opening 62 for delivering test material 10 to elongated chamber 50 therethrough. In some embodiments, one or more of the first light opening 60 and second light opening 61 may be an optical light opening, but not a physical light opening (i.e., may be layer which allows light to be transmitted therethrough.) In other openings, one or more of the first light opening 60 and second light opening 61 may be a physical light opening.
It should be noted that the positioning of any of the at least the first light openings (including first light opening 60, second light opening 61, and third light opening 62) may be disposed on any appropriate surface of optical system 200. In some embodiments, for example, when either the first light opening 60 or second light opening 61 are optical light openings but not physical light openings, the optical light opening may be on any surface of optical system 200. The location and number of openings depicted in the figures and described herein are examples only, and not intended to be limiting in any way. In some embodiments, at least some of the at least the first light opening may be wavelength selective (e.g., have a layer such as a multilayer optical film over the opening which substantially transmits some wavelengths of light and substantially reflects other wavelengths of light.)
In some embodiments, an innermost surface of at least portions of the one or more walls 30, 40 facing elongated chamber 50 may be hydrophilic. In other embodiments, an innermost surface of at least portions of the one or more walls 30, 40 facing elongated chamber 50 may be hydrophobic.
In some embodiments, for the at least the first wavelength, the one or more walls 30, 40 may have an optical reflectance of greater than about 50%, or about 60%, or about 70%, or about 80%, or about 90%, or about 95% for incident angles θ of up to at least 40, degrees, or at least 45 degrees, or at least 50 degrees, or at least 55 degrees, or at least 60 degrees, or at least 65 degrees, or at least 70 degrees. In some embodiments, for the at least the first wavelength, the one or more walls 30, 40 may not exhibit a decrease in reflectance as a function of angle.
In some embodiments, at least one of the one or more light opening may have an optical transmittance of greater than about 50%, or greater than about 60%, or greater than about 70%, or greater than about 80%, or greater than about 90%, or greater than about 95%, for at least one incident angle α, α′.
In some embodiments, the optical system 200 may further include a light source 70 configured to emit light 71 having the at least the first wavelength. In such embodiments, light source 70 may be proximate one of light openings 60, 61 (e.g., light opening 61, as shown in
In some embodiments, the one or more walls 30, 40 may include a metal layer 31, 41, extending substantially along the length L of elongated hollow structure 20. In some embodiments, at least one of metal layer 31, 41 may be configured to come into physical contact, or near physical contact, with test material 10. In other embodiments, at least one of metal layer 31, 41 may be embedded in the one or more walls 30, 40 so as not to make contact with test material 10. For example, as shown in
In other embodiments, such as the embodiment of
In some embodiments, at least some of microlayers 32, 33 in the plurality of microlayers may include an inorganic material. In some such embodiments, the inorganic material may include one or more of an oxide, a nitride, a carbide, and a metal. In some embodiments including an oxide, the oxide may include one or more of a metal oxide, silicon oxide, silicon dioxide, zirconium oxide, and titanium oxide. In some embodiments including a nitride, the the nitride may include one or more of silicon nitride, zirconium nitride, and titanium nitride. In some embodiments including a carbide, the carbide may include one or more of silicon carbide and germanium carbide. In some embodiments including a metal, the metal may include one or more of gold, silver, and aluminum. In some embodiments, at least some of the microlayers in the plurality of microlayers may include an organic material. In some such embodiments, the organic material may include a polymer.
In some cases, the plurality of first layers 32, 33 may include a plurality of alternating first polymeric A layers 32 and first polymeric B layers 33. The first polymeric A layers 32 may be substantially isotropic, i.e., refractive indices along two orthogonal in-plane directions are similar (nx ≈ ny) and the first polymeric B layers 33 may be substantially birefringent (i.e., nx ≠ ny. for example, the first polymeric A and first polymeric B layers 32, 33 may be designed using alternating layers of birefringent PEN and isotropic PMMA. Other combinations of high and low index materials may be used, such as alternating PET and PMMA layers.
In some other cases, the plurality of first layers 32, 33 may include a plurality of vapor deposited alternating first organic 32 and first inorganic 33 layers. For instance, the first organic layers 32 may include a polymer. For example, the polymeric first layers 32 may include one or more of a polycarbonate (PC), a polymethyl methacrylate (PMMA), a polyethylene terephthalate (PET), CoPMMA with PET, a glycol-modified polyethylene terephthalate (PETG), a polyethylene naphthalate (PEN), PC:PETG alloy, and a PEN/ PET copolymer.
In some embodiments, for the at least the first wavelength, the first light opening 60 may have an optical transmittance of greater than about 60% for the at least one incident angle α and the second light opening 61 may have an optical reflectance of greater than about 60% for at least one incident angle β. In some such embodiments, optical system 200 may not include a light opening (e.g., second light opening 61) proximate the second end 34b, 42b of the one or more walls 30, 40 (e.g., such that emitted light 71 is substantially reflected from layer 41 and not transmitted).
In some embodiments, as shown in
In some embodiments, optical system 300 may further include at least one light source 110 disposed proximate one end 53a of the longitudinal ends 53a, 53b of main channel 50. In some embodiments, light source 110 may be configured to emit light 111 having the at least the first wavelength. In some embodiments, optical system 300 may further include at least one detector 120 disposed proximate the other one end 53b of the longitudinal ends 53a, 53b of main channel 50. In some embodiments, detector 120 may be configured to detect emitted light 111. In some embodiments, the at least one detector 111 may include one or an array of a charged coupled device (CCD), a charge injection device (CID), a photodiode, an organic photodiode (OPD), a complementary metal-oxide-semiconductor (CMOS), and a thin-film transistor (TFT). In some embodiments, test material 10 may be configured to change an optical intensity of the emitted light 111, and wherein at least one of the detectors 120 may be configured to detect the change in the optical intensity of emitted light 111. The locations of both light source 110 and detector 120 as shown in the figures and described herein is not intended to be limiting. Additional locations and relative configurations for the light source 110 and detector 120 may be possible within the scope and intent of this description. In some embodiments, light source 110 and detector 120 may be disposed on the top or bottom of the plane of the main channel 50, or in any other appropriate location.
In some embodiments, an optical characteristic of test material 10 may be measured and/or observed at different branch channels 90 along the length of main channel 50 to determine a condition of the test material 10 at each branch channel 90. For example, a color of each branch channel 90 along the length of main channel 50 may be observed and compared to the colors of other branch channels 90 to determine an amount of optical absorbance seen at each branch channel 90. For example, as shown in
It should be noted that, in some embodiments, optical system 300 may not include a detector 120. In such embodiments, the optical characteristics of test material 10 may be observed by examining the conditions visually (e.g., by the human eye, or an external detection system) at each of the branch channels 90 along the length of main channel 50.
Terms such as “about” will be understood in the context in which they are used and described in the present description by one of ordinary skill in the art. If the use of “about” as applied to quantities expressing feature sizes, amounts, and physical properties is not otherwise clear to one of ordinary skill in the art in the context in which it is used and described in the present description, “about” will be understood to mean within 10 percent of the specified value. A quantity given as about a specified value can be precisely the specified value. For example, if it is not otherwise clear to one of ordinary skill in the art in the context in which it is used and described in the present description, a quantity having a value of about 1, means that the quantity has a value between 0.9 and 1.1, and that the value could be 1.
Terms such as “substantially” will be understood in the context in which they are used and described in the present description by one of ordinary skill in the art. If the use of “substantially equal” is not otherwise clear to one of ordinary skill in the art in the context in which it is used and described in the present description, “substantially equal” will mean about equal where about is as described above. If the use of “substantially parallel” is not otherwise clear to one of ordinary skill in the art in the context in which it is used and described in the present description, “substantially parallel” will mean within 30 degrees of parallel. Directions or surfaces described as substantially parallel to one another may, in some embodiments, be within 20 degrees, or within 10 degrees of parallel, or may be parallel or nominally parallel. If the use of “substantially aligned” is not otherwise clear to one of ordinary skill in the art in the context in which it is used and described in the present description, “substantially aligned” will mean aligned to within 20% of a width of the objects being aligned. Objects described as substantially aligned may, in some embodiments, be aligned to within 10% or to within 5% of a width of the objects being aligned.
All references, patents, and patent applications referenced in the foregoing are hereby incorporated herein by reference in their entirety in a consistent manner. In the event of inconsistencies or contradictions between portions of the incorporated references and this application, the information in the preceding description shall control.
Descriptions for elements in figures should be understood to apply equally to corresponding elements in other figures, unless indicated otherwise. Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations can be substituted for the specific embodiments shown and described without departing from the scope of the present disclosure. This application is intended to cover any adaptations or variations of the specific embodiments discussed herein. Therefore, it is intended that this disclosure be limited only by the claims and the equivalents thereof.
| Number | Date | Country | |
|---|---|---|---|
| 63324697 | Mar 2022 | US |
