Circuit board with built-in light source

Abstract

A reagent analyzer is disclosed that includes a circuit board, an imaging system, and a processor. The circuit board includes a substrate and a plurality of conductive leads. The substrate has first and second major surfaces. The first major surface is located opposite the second major surface. The substrate has an opening extending between the first and second major surfaces. The reagent analyzer also includes an imaging system having a field of view extending through the opening formed in the substrate and configured to capture an image of a wet reagent test device positioned at a read position within the field of view, the image having a plurality of pixels. The processor is configured to receive the image and analyze the pixels of the image to determine the presence or absence of a target component in a sample applied to the wet reagent pad.

Description

Technical Field

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 064,609, filed Aug. 12, 2020, and U.S. Provisional Patent Application No. 63 / 225,124, filed Jul. 23, 2021, under 35 U.S.C. § 119(e). The entire contents of the patent applications referenced above are hereby incorporated by reference into this specification.

[0002] The inventive concept disclosed herein generally relates to an analyzer for reagent cards, and more particularly, but not limited to, an analyzer having an improved signal-to-noise ratio by using a circuit board having an opening and a built-in light source.

Background Art

[0003] To meet the needs of the medical community and other expanding technologies such as the brewing industry and chemical manufacturing, numerous analytical procedures, compositions, and tools have been developed, including lateral flow immunoassays and so-called "dip and read" reagent test devices. Whether a lateral flow immunoassay or dip and read test device is used for the analysis of biological fluids or tissues, or for the analysis of commercial or industrial fluids or substances, the general procedure involves the test device contacting the sample or specimen to be tested and the test device being analyzed manually or by instrumentation.

[0004] A lateral flow immunoassay is a diagnostic device used to confirm the presence or absence of a target analyte. A lateral flow immunoassay generally includes a flow path that transports a sample across a control line position and a test line position. The control line at the control line position determines that the test is functioning properly, and the test line at the test line position provides the result of the lateral flow immunoassay. Lateral flow immunoassays are developed to be used in a dipstick format or a home test format. Both dipsticks and home tests function similarly and generally fall into one of two categories: a sandwich assay where a positive test is indicated by the presence of a colored line at the test line position, and a competitive assay where a positive test is indicated by the absence of a colored line at the test line position.

[0005] Dip-and-read reagent test devices are widely used in many analytical applications, particularly in the chemical analysis of biological fluids, because they are relatively low-cost, easy to use, and provide rapid results. For example, in the medical field, a dip-and-read reagent test device can be immersed in a sample of body fluid or tissue such as urine or blood, and a number of physiological functions can be monitored simply by observing a detectable response such as a color change or a change in the amount of light reflected or absorbed by the test device.

[0006] Many dip-and-read reagent test devices for detecting components of body fluids are capable of making quantitative or at least semi-quantitative measurements. Thus, by measuring the detectable response after a predetermined time, the user can obtain not only a positive indication of the presence of a particular component in the test sample, but also an estimate of how much of that component is present. Such dip-and-read reagent test devices provide an easy diagnostic tool and the ability to assess the degree of a disease or physical disorder to physicians and laboratory technicians.

[0007] Examples of currently used dip-and-read reagent test devices include products available from Siemens Healthcare Diagnostics Inc. under the MULTISTIX trademark. Such immuno-chemical, diagnostic, or serological test devices typically include one or more carrier matrices such as absorbent paper, and such carrier matrices incorporate specific reagents or reaction systems that exhibit a distinct response (e.g., a color change within the visible or ultraviolet spectrum) detectable in the presence of specific test sample components or ingredients. Depending on the reaction system incorporated into a particular matrix, these test devices can detect the presence of glucose, ketones, bilirubin, urobilinogen, occult blood, nitrite, and other substances. The distinct change in the intensity of the color observed within a specific time range after contacting the dip-and-read reagent test device with a sample indicates the presence and / or concentration of specific components in the sample. Some other examples of dip-and-read reagent test devices and their reagent systems can be found in Patent Document 1, Patent Document 2, and Patent Document 3, the entire disclosures of which are incorporated herein by reference.

[0008] However, dip-and-read reagent test devices have several limitations. For example, in the case of dip-and-read reagent test devices, generally, a technician has to manually immerse the test device into the sample, wait for a specified amount of time, and visually compare the color of the test device with a color chart provided with the test device. This process is slow, and the resulting readings are dependent on advanced techniques (e.g., accurate timing, proper comparison with the color chart, ambient lighting conditions, and the technician's eyesight), and the results may not be consistent between two different technicians performing the same test. Finally, the act of manually immersing the test device into the sample can lead to cross-contamination or improper deposition of the test sample on the test device, such as incomplete insertion of the test device into the sample, insufficient time to deposit the sample on the test device, or too much sample on the test device dripping, leaking, or splashing onto the technician's work area, person, or clothing.

[0009] In particular, test tools and methods for performing multiple tests economically and rapidly have been sought in the art by using automated processes. Automated analyzer systems have advantages over manual tests with respect to the cost per test, throughput of the tests, and / or the speed at which test results or other information are obtained.

[0010] In the case of current available automated instruments for reading individual reagent test devices, such as lateral flow immunoassay or dip-and-read reagent test devices or reagent strips (e.g., CLINITEK STATUS reflectance photometer manufactured and sold by Siemens Healthcare Diagnostics, Inc.), it is necessary to manually load each test device onto the automated instrument after contacting the test device with the specimen or sample to be tested. For manual loading, it is necessary to properly place the reagent test device on the automated instrument within a limited period after contacting the solution or substance to be tested. When the analysis is completed, the used reagent test device is removed from the instrument and discarded in accordance with the applicable regulations.

[0011] Another development example is to introduce a multi-profile reagent card and an automatic analyzer for the multi-profile reagent card. The multi-profile reagent card is an essentially card-shaped test device that includes a plurality of reagent-impregnated matrices or pads for performing multiple analyses of an analyte simultaneously or sequentially, as described, for example, in Patent Document 4, which is hereby incorporated by reference in its entirety. The reagent pads on the multi-profile reagent card are typically arranged in a grid pattern so as to define several rows and columns of reagent pads and are spaced apart from each other. Adjacent reagent pads within the same row can be referred to as, for example, test strips and can contain reagents for a preset combination of tests to be performed on each sample.

[0012] A multi-profile reagent card provides an efficient, economical, rapid, and convenient way to perform automated analysis. An automated analyzer configured to use a multi-profile reagent card typically retrieves the multi-profile reagent card from a storage drawer or cassette, etc., and advances the multi-profile reagent card step by step, typically one step at a time, on the advancing surface of the analyzer via a card movement mechanism, and places one test strip (or one row of reagent pads) at the sample dosing position and / or one or more reading positions. Exemplary card movement mechanisms include a conveyor belt, a ratchet mechanism, a sliding ramp, or a card gripping or pulling mechanism. When the multi-profile reagent card moves or advances along the advancing surface and is placed at the sample dosing position, one or more pipettes deposit (e.g., manually or automatically) the volume of one or more samples onto one or more of the reagent pads on the reagent card. Next, the reagent pads are placed at one or more reading positions and analyzed (e.g., manually or automatically) to evaluate the test results. The reagent card is placed within the field of view of an imaging system such as, for example, an optical imaging system, a microscope, or a spectrometer, and one or more images (e.g., optical signals indicating the color of the reagent pads) of the reagent pads on the card are captured and analyzed. Typically, the field of view of the imaging system is relatively large, and when the reagent card is moved or advanced across multiple reading positions within the field of view of the imaging system, it is possible to capture multiple images of the same reagent pad. The field of view includes multiple reading positions or locations, and as the reagent card progresses through the field of view of the imaging system, each reagent pad moves stepwise through these reading positions. Since the analyzer moves the card between various reading positions at known time intervals, for example, based on the time it takes for the pad to move to each reading position as indicated by multiple images obtained within the field of view of the imaging system, the analyzer can determine the change in color of the reagent pad as a result of the reaction of the reagent pad with the sample at each reading position. Finally, the used card is removed from the analyzer and appropriately discarded.

[0013] Existing problems associated with optical imaging systems used with automated analyzers are that the illumination of the relatively large field of view of the optical imaging system is non-uniform, vignetting effects occur in the lenses of the cameras used, noise occurs due to the large aspect ratio of the reagent test device, and light scatters between the test device and the imaging system. Due to these factors, the image may become non-uniform. However, one of these requirements for most colorimetric analysis modules is to make the illumination intensity uniform within the image acquired across the test device. However, correction using image processing does not improve the signal-to-noise ratio (SNR). Light scattering within existing optical imaging systems can further reduce the signal-to-noise ratio by introducing noise into the image.

[0014] Specular reflection is a mirror reflection from the surface and is not related to the material below the surface. Within the analyzer, specular reflection can occur due to the surface of the test sample and / or test device being wet. When specular reflection occurs, such specular reflection can cause measurement confusion due to bright mirror reflection spots that are not related to the signal resulting from the absorption of light in the reagent pad. Specular scattering interferes with the measurement of the reflected light from the reagent pad by adding an irrelevant variable signal that is not related to the analyte concentration, making the measurement related to the analyte concentration inaccurate. Crossed polarizers for reducing interference due to specular reflection are discussed in Patent Document 5.

Prior Art Documents

Patent Documents

[0015]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Summary of the Invention

Problems to be Solved by the Invention

[0016] Therefore, there is a need in the art for an analyzer that provides controlled illumination and increases the signal-to-noise ratio by reducing the effects of light scattering. The inventive concept disclosed herein is directed to such a reagent analyzer.

Means for Solving the Problems

[0017] In one embodiment, the inventive concept disclosed herein is a reagent analyzer that addresses the deficiencies of the prior art described above. The reagent analyzer has a circuit board, an imaging system, and a processor. The circuit board has a substrate and a plurality of conductive leads extending on or within the substrate. The substrate has a first major surface and a second major surface, and the first major surface is located opposite the second major surface. The substrate has an opening extending between the first major surface and the second major surface. The reagent analyzer also includes an imaging system that has a field of view extending through an opening formed in the substrate and is configured to capture an image of a wet reagent test device disposed at a reading position within the field of view, the image having a plurality of pixels. The processor is configured to receive the image and analyze the pixels of the image to determine the presence or absence of a target component in a sample added to the wet reagent pad.

[0018] To assist those skilled in the art in making and using the inventive concept disclosed herein, reference is made to the accompanying drawings and schematic diagrams, which are not intended to be drawn to scale, and like reference numerals are intended to refer to the same or similar elements for consistency. For clarity, not all components are shown in all of the drawings. For clarity and brevity, the specific configurations and specific appearances of these figures may not be drawn to scale and may be shown emphasized or schematically.

Brief Description of the Drawings

[0019]

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DETAILED DESCRIPTION OF THE INVENTION

[0020] Before describing in detail at least one embodiment of the inventive concept disclosed herein, it should be understood that the inventive concept is not limited in its application to the details of the components or steps or the structure and arrangement of the methods described in the following description or shown in the drawings. The inventive concept disclosed herein can have other embodiments or can be implemented or carried out in various ways. Also, it should be understood that the terms and phrases used herein are for the purpose of description and should not be construed as limiting the inventive concept disclosed and claimed herein in any way.

[0021] In the following detailed description of embodiments of the inventive concept, numerous specific details are set forth in order to provide a more thorough understanding of the inventive concept. However, it will be apparent to those skilled in the art that the inventive concept disclosed herein can be practiced without these specific details. In other instances, well-known structures are not described in detail so as not to unnecessarily obscure the present disclosure.

[0022] As used herein, the terms "comprises," "comprising," "includes," "including," "has," "having," or any other variation thereof are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent thereto.

[0023] Unless the contrary is explicitly stated, "or" refers to an inclusive disjunction rather than an exclusive disjunction. For example, the condition "A or B" is satisfied by any one of the states where A is true (or present) and B is false (or absent), where A is false (or absent) and B is true (or present), and where both A and B are true (or present).

[0024] In addition, the use of "a" or "an" is used to describe the elements and components of the embodiments herein. This is done only for convenience to give a general sense of the inventive concept. This description should be construed to include one or at least one, and the singular includes the plural unless it is clear that it means something else.

[0025] Further herein, any reference to "an embodiment" or "embodiments" means that the particular elements, configurations, structures, or characteristics described in connection with that embodiment are included in at least one embodiment. References to the phrase "in one embodiment" in various places herein do not necessarily refer to the same embodiment.

[0026] As used herein, a "wet reagent test device" refers to a reagent device on which a volume of sample is deposited, and the reagent within the reagent device is capable of reacting with its target component if such a component is present in the sample. A wet reagent test device can also deposit a negative control volume.

[0027] As used herein, a "reagent test device" refers to a carrier having a reagent. Exemplary reagent devices include the reagent pads of dip-and-read test strips, or the control strips or test strips of lateral flow immunoassays.

[0028] Finally, as used herein, modifiers such as "about", "approximately", and "substantially" are intended to mean that the item so modified is not limited to the specified exact value and includes minor variations or deviations from that value caused, for example, by measurement error, manufacturing tolerances, stresses applied to various components, wear, and combinations thereof.

[0029] The concepts of the inventions disclosed herein generally relate to analyzers for reagent cards, and more particularly, but not limited to, analyzers that provide controlled illumination within acceptable limits and increase the signal-to-noise ratio by reducing the effects of light scattering. Examples of controlled illumination include, but are not limited to, uniform illumination within acceptable limits, spots, flashes, or illumination that varies over time. The concepts of the inventions disclosed herein will be described primarily in relation to automated analyzers that use multi-profile reagent cards, but the concepts of the inventions disclosed herein are not limited to automated analyzers or multi-profile reagent cards. For example, as will be understood by those skilled in the art who would benefit from the present disclosure, the methods according to the concepts of the inventions disclosed herein can be implemented by a manual analyzer or by an automated analyzer that uses reagent test devices such as lateral flow immunoassay, dip-and-read reagent test devices, or reels of reagent test devices on a substrate, and combinations thereof. Further, the concepts of the inventions disclosed herein can be implemented by any reagent device imaging system having at least one reading position within the field of view.

[0030] In particular, when a reagent test device is wet, the signal value indicating the color of the reagent test device, such as a reagent pad, control line, or test line, changes. In the case of a negative solution, the change in the signal value is known (or can be measured) and can thus be an optional offset signal value. Any change outside the range of the offset signal value is likely to be caused by a reaction with the clinical component being measured.

[0031] Next, referring to FIGS. 1-2, an exemplary embodiment of a reagent analyzer 10 according to the concepts of the invention disclosed herein is shown. The reagent analyzer 10 can be, for example, an automated reagent card analyzer. Exemplary embodiments of automated reagent card analyzers are described in detail in U.S. Patent Application No. 13 / 712,144, filed December 12, 2012, and PCT Application PCT / US2012 / 069621, filed December 14, 2012, the entire disclosures of which are hereby expressly incorporated herein by reference.

[0032] Generally, the reagent analyzer 10 can include a housing 14 that surrounds a cavity 18, an imaging system 22 that includes at least a camera 26, a sample tray 30 that has a sample holder 32 disposed within the cavity 18, and a circuit board 34 that has an opening 38 (also referred to as a first opening) and one or more illumination sources 42a-n and is disposed within the cavity 18.

[0033] The housing 14 can be formed from one or more components configured to form the cavity 18 and support the imaging system 22, the sample tray 30, and the circuit board 34. In one embodiment, the housing is opaque to visible light. In another embodiment, the housing is opaque to one or more wavelengths of light generated by one or more of the illumination sources 42a-n. In one embodiment, the housing 14 can normalize ambient light.

[0034] The imaging system 22 includes at least one camera 26 and is supported by the housing 14. In one embodiment, the imaging system 22 can be fixed, for example, to the housing 14 or fixed at a relative distance from the sample tray 30. The imaging system 22 and / or the camera 26 can include one or more lenses having a focal length selected to provide a field of view 40 to include at least the opening 38 of the circuit board 34.

[0035] The imaging system 22 can be implemented and function as any desired reader, for example, such that the field of view 40 of the imaging system 22 substantially encompasses the entirety of the opening 38 of the circuit board 34. The imaging system 22 can be supported above, below, or adjacent to the sample tray 30. In some embodiments, the field of view 40 can extend linearly from the imaging system 22 to the opening 38. In other embodiments, the field of view 40 can extend non-linearly from the imaging system 22 to the opening 38 due to the presence of one or more optical steering components within the field of view 40. Exemplary optical steering components include mirrors, lenses, beam splitters, or combinations thereof. The imaging system 22 can be configured to detect or capture an image or optical signal indicative of the reflectance value or color value of a reagent pad disposed within the field of view 40 of the imaging system 22 (shown in FIG. 6 and discussed in more detail below). However, it should be understood that in some exemplary embodiments, the field of view 40 of the imaging system 22 can also include only a portion of the opening 38 of the circuit board 34. The camera 26 of the imaging system 22 can include any desired digital or analog imaging device, such as a digital camera, an analog camera, a CMOS imaging device, a diode, and combinations thereof. The imaging system 22 can also include, for example, a lens system, an optical filter, a collimator, a diffuser, or any other optical signal processing device. Furthermore, the imaging system 22 is not limited to optical imaging devices within the visible spectrum and can include, for example, an infrared imaging system, an ultraviolet imaging system, a microwave imaging system, an X-ray imaging system, and / or other desired imaging systems. Non-exclusive examples of the imaging system 22 include, for example, an optical imaging system, a spectrophotometer, a gas chromatograph, a microscope, an infrared sensor, and combinations thereof.

[0036] In one embodiment, the imaging system 22 includes at least one camera 26 and a lens. The at least one camera 26 is an OnSemi MT9D131 CMOS sensor (ON Semiconductor, Phoenix, Arizona), and the lens is a DSL949 Sunex lens (Sunex Inc., Carlsbad, CA). Both are configured to maintain a wide field of view 40 while suppressing geometric image distortion, thereby providing a resolution of 1600 pixels × 1200 pixels. Each pixel represents an area of approximately 0.065 mm square of the sample tray 30 and / or the sample holder 32.

[0037] The sample tray 30 can be configured to adjust the location of the sample holder 32 within the field of view 40. The sample holder 32 can be configured to receive at least one of the test devices 44, which can be reagent cards and reagent card cassettes, each having a sample 46. The sample 46 can be any body fluid, tissue, or any other chemical or biological sample, such as urine, saliva, or blood, and combinations thereof. The sample 46 can be, for example, in a liquid state and can contain one or more target components such as bilirubin, ketone, glucose, or any other desired target component.

[0038] The circuit board 34 having the opening 38 can be disposed within the cavity 18 and placed between the imaging system 22 and the sample tray 30. Thus, the field of view 40 of the imaging system 22 is substantially unobstructed by the sample holder 32, the test device 44, and / or the sample 46. The circuit board 34 will be described in more detail with reference to FIG. 3 and below. In one embodiment, the circuit board 34 is disposed at a fixed location between the imaging system 22 and the sample tray 30, but in another embodiment, the circuit board 34 can also be adjusted to a varying location between the imaging system 22 and the sample tray 30. If the circuit board 34 is adjustable, a calibration routine 170 (described below) must be executed after any adjustment.

[0039] The illumination sources 42a - n can be implemented as, for example, one or more of a light - emitting diode, a light bulb, a laser, an incandescent bulb or tube, a fluorescent bulb or tube, a halogen bulb or tube, or any other desired light source or object configured to emit an optical signal having any desired intensity, wavelength, frequency, or propagation direction. The illumination sources 42a - n can be attached to the circuit board 34 and oriented such that substantially the entire field of view 40 of the imaging system 22 is illuminated by the illumination sources 42a - n. In some exemplary embodiments, the illumination sources 42a - n can be operably coupled to a controller 144 (see FIG. 7, detailed below), and thus control and / or power signals can be supplied to the illumination sources 42a - n by the controller 144. It is desirable that the intensity of the optical signal emitted by the illumination sources 42a - n be maintained substantially constant over the operation of the reagent analyzer 10, such as by control and power signals supplied by the controller 144. In one embodiment, the optical signal emitted by the illumination sources 42a - n can be adjusted or processed by one or more optical systems or other systems (not shown), such as, for example, filters, diffusers, polarizers, lenses, lens systems, collimators, and combinations thereof.

[0040] In some exemplary embodiments, one or more illumination sources 42a - n, such as a first illumination source 42a and a second illumination source 42b, can be implemented, and the first illumination source 42a and the second illumination source 42b can have different locations and / or orientations, whereby the first illumination source 42a and the second illumination source 42b cooperate to illuminate substantially the entire field of view 40 of the imaging system 22 (e.g., substantially the entire sample holder 32 and / or the sample 46). The first illumination source 42a and the second illumination source 42b can emit optical signals having, for example, different illumination intensities.

[0041] In one embodiment, the sample holder 32 can be adapted to receive a test device 44 in the form of, for example, a reagent card cassette having one or more multi-profile reagent cards. Each reagent card (detailed below) can include a substrate and one or more reagent pads, and the reagent pads are disposed on or otherwise associated with the substrate. In an exemplary embodiment, the reagent pads can include fluid or microfluidic compartments (not shown).

[0042] Each reagent pad can include a reagent configured to produce a color change in response to the presence of a target component, such as a molecule, cell, or substance, in the sample 46 of the analyte deposited on the reagent pad. Different reagents can be provided to the reagent pads to detect the presence of different target components. The different reagents can cause one or more color changes in response to the presence of a specific component in the sample 46, such as a specific type of analyte. The color produced by the reaction of a specific component with a specific reagent can define an individual spectrum characteristic of the light absorption and / or reflection for that specific component. The degree of color change of the reagent and the sample 46 can depend, for example, on the amount of the target component present in the sample 46.

[0043] The presence and concentration of these target components in the sample 46 can be made determinable, for example, by analysis of the color change produced by one or more reagent pads after a predetermined time after adding the sample 46 to the reagent pads and / or at a predetermined reading position within the field of view of the imaging system 22. This analysis can involve color comparison of each reagent pad at different times after adding the sample 46 and / or at different reading positions within the field of view 40 of the imaging system 22.

[0044] Based on the analysis of the magnitude of the optical signal detected by the imaging system 22, for example, a first category corresponding to the absence of a target component in the sample 46, a second category corresponding to a low concentration of the target component present in the sample 46, a third category corresponding to a medium concentration of the target component present in the sample 46, and a fourth category corresponding to a high concentration of the target component present in the sample 46, the sample 46 can be assigned to one of a plurality of categories.

[0045] Furthermore, the imaging system 22 can detect an optical signal indicating the color or reflection value of the reagent pad and / or test strip at any time interval after the volume of the sample 46 is dispensed onto the test device 44, such as a reagent pad and / or test strip, regardless of the location of the specific reagent pad and / or test strip. In one exemplary embodiment, videos or a series of images of the reagent pad and / or test strip can be captured at various time intervals after the volume of the sample 46 is deposited on the reagent pad and / or test strip.

[0046] The imaging system 22 can be operated intermittently, continuously, or periodically to detect one or more reflection signals indicating the color or reflection value of one or more test devices 44, such as a reagent pad, at any time and at any position within the field of view of the camera 26. In some exemplary embodiments, the imaging system 22 can capture an image of the test device 44, such as the color or reflection value of the reagent pad, before any sample 46 is deposited on the reagent pad or at any known point in time after the volume of the sample 46 is deposited on the reagent pad.

[0047] Next, referring to FIG. 3, a bottom view of a circuit board 34 having an opening 38 surrounded by one or more light sources 42a - n according to the concepts of the invention disclosed herein is shown to facilitate controlled illumination of the sample holder 32 and / or the sample 46 and to reduce light scattering detected by the imaging system 22. For controlled illumination, by way of example herein, it is described as uniform illumination over the extent, i.e., length and width, of the sample holder 32 and / or the sample 46 within acceptable limits. However, it should be understood that the present disclosure is not limited to uniform illumination. The circuit board 34 includes a substrate 60 having a bottom surface 61a and a top surface 61b, a plurality of conductive leads extending on or within the substrate 60, and an opening 38 extending between the bottom surface 61a and the top surface 61b.

[0048] The circuit board 34 shown in FIG. 3 represents the bottom surface 61a of the circuit board 34 having one or more illumination sources 42a. When disposed within the reagent analyzer 10, the bottom surface 61a is oriented to face the sample tray 30, and thus light generated by one or more illumination sources 42a-n can be provided directly to the sample holder 32 and / or the sample 46. The illumination sources 42a-n are connected to a plurality of conductive leads of the circuit board 34, and thus the conductive leads provide electricity to each illumination source 42a-n. In one embodiment, the circuit board 34 further includes an illumination source circuit (not shown) connected to the plurality of conductive leads, and the illumination source circuit is configured to apply electricity regardless of each illumination source 42a-n. For example, the illumination source circuit can be configured to supply a first power to the first illumination source 42a and a second power to the second illumination source 42b, and the first power and the second power are different, thereby causing a difference in illumination intensity across the sample. The illumination sources 42a-n are arranged such that the illumination intensity is substantially uniform across the field of view 40 of the camera 26, thereby illuminating the reagent pad with a substantially uniform intensity, increasing the accuracy of reading the color change of the reagent pad (shown in more detail below and in FIG. 5). As shown in FIG. 3, the substrate 60 of the circuit board 34 is substantially planar, whereby each of the one or more illumination sources 42a-n is positioned at a similar distance from the sample tray 30. Depending on the location of the illumination sources 42a-n relative to the sample 46, the distance between some of the illumination sources 42a-n and the sample 46 may be different. However, in other embodiments, the circuit board 34 can be non-planar, whereby one or more of the illumination sources 42a-n are positioned at different distances from the sample tray 30. In one embodiment, one or more illumination sources 42a-n can be attached to a support (not shown), and each support is attached to the circuit board 34 to provide one or more conductive paths to a particular one of the illumination sources 42a-n. When the support is used, this causes a portion of one or more illumination sources 42a-n to approach the sample 46 and / or the sample tray 30.

[0049] In one embodiment, the substrate 60 has a first region 62a, a second region 62b located opposite the first region 62a, and an intermediate region 62c located between the first region 62a and the second region 62b. One or more illumination sources 42a - n can be attached to the substrate 60 in each of the first region 62a, the second region 62b, and the intermediate region 62c, or in some combination thereof. In one embodiment, a first power can be applied to one or more of the illumination sources 42a - n in the first region 62a and the second region 62b, whereby one or more of the illumination sources 42a - n in the first region 62a and the second region can provide a first illumination intensity, and a second power can be applied to one or more of the illumination sources 42a - n in the intermediate region 62c, whereby one or more of the illumination sources 42a - n in the intermediate region 62c can provide a second illumination intensity. The first power and the second power are different, and the first illumination intensity and the second illumination intensity are different.

[0050] The opening 38 extends from the top surface 61b to the bottom surface 61a, provides an aperture for the field of view 40 of the imaging system 22 to pass from the imaging system 22 to the sample holder 32, and provides a controlled field of view of the test device 44 associated with the sample holder 32 to the camera 26. The opening 38 can be further configured such that the bottom surface 61a of the circuit board 34 can include one or more illumination sources 42a - n on each side of the opening 38. In one embodiment, the opening 38 is located substantially within the intermediate region 62c. In one embodiment, the opening 38 has a first major axis and a first minor axis, the sample holder 32 has a second major axis and a second minor axis, and the first major axis is aligned with the second major axis. In order to provide a controlled field of view of a rectangular reagent test device, the opening 38 is shown as rectangular in FIG. 3, but the opening 38 can be configured in any shape such that the field of view 40 is a controlled field of view of the sample tray 30, and it is understood that the illumination source 42 can be calibrated to provide substantially uniform illumination of the sample 46. In the example of FIG. 3, the opening 38 does not extend to the edge of the circuit board 34.

[0051] In one embodiment, the opening 38 extends to the edge of the circuit board 34 without bisecting the circuit board 34. In another embodiment, the opening 38 extends through the entire circuit board 34, bisecting the circuit board into a first half and a second half. The first half and the second half are attached at separate locations and are supported by the housing 14 such that the field of view 40 is a controlled field of view of the sample tray and the illumination source 42.

[0052] In one embodiment shown in FIG. 3, one or more illumination sources 42a - n are a plurality of LEDs 64a - n and one or more infrared LEDs 68a - n. The LEDs 64a - n shown in FIG. 3 include 20 visible light LEDs arranged as shown in FIG. 3 and one or more infrared LEDs 68. The LEDs 64a - n include any LEDs required to produce a substantially uniform light intensity across the sample holder 32 and / or the reagent card or reagent cassette. The infrared LEDs 68 can be used, for example, to apply heat to the sample 46 or to identify the ID pad on the test device 44. In one embodiment, the ID pad is utilized to correlate the sample on the test device supported by the sample holder 32 with the data acquired by the reagent analyzer 10.

[0053] In one embodiment, the plurality of LEDs 64a - n are selected to provide a fixed color, visible light, ultraviolet light, infrared light, or white light, or some combination thereof. In another embodiment, each LED 64a - n is arranged obliquely with respect to the reagent card. In yet another embodiment, each LED 64a - n is arranged at one or more distances from the test device 44 supported by the sample holder 32, such that the first LED 64 and the second LED 64 are located at different distances from the test device 44 and / or the sample holder 32.

[0054] Next, referring to FIGS. 4-5, FIG. 4 shows a table 80 indicating a power level 84, an x-position 88, a y-position 90, a z-position 92, and a relative angle 94, where the relative angle 94 is the angle with respect to the sample holder 32 for each of the LEDs 64a-t. FIG. 5 shows a diagram showing an illumination intensity graph 100, where the optimized normalized illumination intensity measurement 104 shows the optimization of the LEDs 64a-t, and the non-optimized illumination intensity measurement 108 shows the LEDs 64a-t that have not been optimized according to the inventive concept disclosed herein. By adjusting the power level of each LED 64, the substantially uniform light intensity shown in the optimized illumination intensity measurement 104 is achieved. The substantially uniform light intensity can be 85% to 100% uniform. In the example shown in FIG. 5, the optimized normalized illumination intensity is 85% to 95%.

[0055] Next, referring to FIG. 6, FIG. 120 of a portion of an exemplary test device 44 in the form of a reagent card 124 that can be read by a reagent analyzer 10 according to the inventive concept disclosed herein is shown.

[0056] The reagent card 124 can include a substrate 128 and one or more or a plurality of reagent pads 132a-n, and the reagent pads 132a-n are disposed on the substrate 128 or otherwise associated with the substrate 128. The substrate 128 can be constructed from any suitable material such as, for example, paper, photographic paper, polymers, fibrous materials, and combinations thereof. The reagent pads 132a-n can be disposed on the substrate 128 in a grid configuration, for example, so as to define one or more test strips. In an exemplary embodiment, the reagent pads 132a-n can include fluids or microfluidic compartments (not shown). The reagent pads 132a-n can be spaced apart from each other, for example, such that the test strips are spaced apart and thus the adjacent test strips and / or reagent pads 132a-n can be simultaneously disposed at separate positions within the field of view 40 of the imaging system 22. The reagent card 124 can be a multi-profile reagent card having a plurality of reagent pads 132a-n with different reagents and / or a plurality of different test strips. Further, in some exemplary embodiments, the reagent card 124 can include, for example, one or more calibration chips or reference pads, such calibration chips or reference pads having no reagents and being able to act as color references. In another embodiment, the reagent card 124 includes an ID pad having an identifier that can be seen under infrared light.

[0057] Each of the reagent pads 132a - n can contain a reagent configured to cause a color change in response to the presence of a target component such as a molecule, cell, or substance in the sample 46 deposited on the reagent pads 132a - n. Different reagents can be provided to the reagent pads 132a - n to detect the presence of different target components. The different reagents can cause one or more color changes in response to the presence of a specific component in the sample 46, such as a particular type of analyte. The color resulting from the reaction of a specific component with a specific reagent can define an individual spectrum characteristic of the light absorption and / or reflection for that specific component. The degree of color change of the reagent and the sample can depend, for example, on the amount of the target component present in the sample 46.

[0058] The color change can be read by the imaging system 22. Signals indicating the color of the reagent pads 132a - n can be received by the imaging system 22, which can analyze those signals and determine the color change of the reagent pads 132a - n resulting from the reaction with the volume of the sample 46 deposited on the reagent pads 132a - n. Such a color change can be analyzed, for example, based on the reading position of the reagent pads 132a - n when an optical signal or image indicating the color of the reagent pads 132a - n is detected, and / or the known duration for which the volume of the sample 46 has been deposited on the reagent pads 132a - n, and combinations thereof. The color change can be interpreted, as described above, as a quantitative, qualitative, and / or semi - qualitative indication of the presence and / or concentration or amount of the target component in the volume of the sample 46 deposited on the reagent pads 132a - n.

[0059] Next, referring to FIG. 7, an analyzer diagram 140 is shown representing a reagent analyzer 10 that includes an analyzer controller 144. The analyzer controller 144 has at least a processor 148 and a non-transitory computer-readable memory 152. The memory 152 can store computer-executable instructions that, when executed by the processor 148, cause the processor 148 to communicate with and / or be operably coupled to other elements of the reagent analyzer 10. Although the analyzer controller 144 is shown separately from the reagent analyzer 10, in some embodiments, the analyzer controller 144 can be integrated into the reagent analyzer 10. For example, for illustrative purposes only, the analyzer controller 144 can be an additional component of the reagent analyzer 10 or can be integrated with another component of the reagent analyzer 10, such as circuit board 34.

[0060] In one embodiment, the imaging system 22 can be operably coupled to, for example, the analyzer controller 144 and / or the processor 148, and thus, one or more power and / or control signals can be transmitted by the controller 144 to the camera 126 and / or one or more light sources 42a - n, and one or more signals can be transmitted from the camera 126 to the processor 148. The analyzer controller 144 can be configured to evaluate test results when a reagent card is extracted within the reagent analyzer 10, for example, by receiving one or more signals from the camera 126. The camera 126 can be configured to detect or capture one or more optical signals or other signals indicative of the reflectance value of a test device 44, such as a reagent pad, and transmit a signal indicative of the reflectance value of the test device 44, such as the reagent pad, to the processor 148. For example, the camera 126 can detect one or more optical signals having wavelengths indicative of the reflectance value of the reagent pad and / or test strip at each reading position. The camera 126 can detect optical signals indicative of the reflectance value of the reagent pad and / or test strip at any desired reading position, location, or region within the field of view 40, or at any other desired one or more locations or regions. The signal transmitted by the camera 126 to the processor 148 can be, for example, an electrical signal, an optical signal, and combinations thereof. In one embodiment, the signal is in the form of an image file having a matrix of pixels, with each pixel having a color code indicative of a reflectance value. In an exemplary embodiment, the image file can have pixels in two or more predetermined regions, with the pixels in each predetermined region corresponding to one reading position of the reagent pad and / or test strip within the field of view 40 of the camera 126. In one embodiment, the processor 148 can store the transmitted signal and / or image file in one or more databases 156 and / or memory 152.

[0061] Processor 148 can determine the reflection value or color change of the reagent pad and / or test strip together with a sample (e.g., urine) placed on the reagent pad and / or test strip, based on, for example, the signal detected by camera 126. Each optical signal or other signal indicating the reading of one or more reflection values detected by camera 126 can have magnitudes for different light wavelengths (i.e., colors). The color of the sample and / or the reaction of one or more reagents to the target component in the reagent pad can be determined based on the relative magnitudes of the reflection signals of various color components, for example, the red, green, and blue reflection component signals. For example, the color of each reagent pad can be converted to a standard color model, which typically includes three or four values or color components whose combination represents a specific color (e.g., RGB color model including hue, saturation, and lightness (HLS), and point representations of hue, saturation, and value (HSV), and / or CMYK color model, or any other suitable color model). In some embodiments, camera 126 can detect multiple optical signals at each reading position, and each detected signal can have one or more color components, such as a red component signal, a green component signal, and a blue component signal, and each of these component signals can be transmitted to processor 148. In some exemplary embodiments, for example, camera 126 can detect a single optical signal at each reading position, and processor 148 can convert the signal received from camera 126 into separate color component signals, such as a red component signal, a green component signal, and a blue component signal.

[0062] In one embodiment, the processor 148 selects or otherwise designates a reagent pad as a reference reagent pad, and by using the reference reagent pad as a reference for each of the remaining reagent pads, calculates a calibration coefficient for each reagent pad at each reading position based on the ratio of the reflection value of the optical signal or image detected by the reference reagent pad to the optical signal or image detected by each reagent pad detected by the camera 126. Further, in some exemplary embodiments, instead of selecting a reference reagent pad, as would be understood by those skilled in the art, a conceptual color or color standard for each reagent pad can be used as a reference for each reagent pad.

[0063] The calibration routine 170 (described below and shown in FIG. 8) can be implemented as a set of processor-executable instructions or logic stored in the non-transitory computer-readable medium 154, which, when executed by the processor 148, cause the processor 148 to perform logic to calculate or determine a calibration coefficient. The calibration routine 170 can be performed periodically, for example, at a preset time interval, for each new lot of reagent cards, when desired according to specific quality control procedures applicable to the reagent analyzer 10, and combinations thereof.

[0064] Next, referring to FIG. 8, an exemplary process flow diagram of calibration routine 170 is shown. Calibration routine 170 generally includes: a step of obtaining at least one image of a calibration test strip, wherein only one of one or more light sources is enabled for each image (step 174); a step of preprocessing the image (step 178); a step of updating the "A" matrix with the preprocessed image (step 182); a step of determining the intensity value of each of one or more light sources 42a - n (step 186); a step of generating a light source intensity file (step 190); a step of obtaining a test image of the calibration test strip using the light source intensity file (step 194); and a step of determining a non-uniformity value (step 198). Calibration routine 170 is used to maximize the uniformity of light intensity with the minimum number of required light sources 42a - n and to determine the state of the light sources for each light source 42a - n on circuit board 34. For calibration routine 170, each light source 42a - n is described below as LED 64a - n, but it is understood that each LED 64a - n can also be replaced with other light sources 42a - n. Further, for example, the state of the light source for each LED can be stored as LED state data, which can include data describing the LED, such as intensity, power level, location, LED identifier, and / or combinations thereof.

[0065] In operation 174, camera 126 can detect a first optical signal or a first image indicative of the reflection value of a calibration test strip disposed within sample holder 32 with the first LED 64a enabled and, for example, all other LEDs 64b - t disabled. In an exemplary embodiment, camera 126 can detect an image having a pixel region with a color or reflection value representative of the color of the calibration test strip and transmit such an image to controller 144. Camera 126 can then detect a second optical signal different from the first optical signal or a second image different from the first image indicative of the reflection value at the calibration test strip location within sample holder 32 with the second LED 64b enabled and, for example, all other LEDs 64a and 64c - t disabled. The calibration test strip can be a dry reagent card having one or more dry reagent pads. Each image can include metadata stored in the image, such as an LED identifier associated with the LED 64 in an active state, i.e., a state in which the LED power level is set to a value enabling light generation by the LED. Since no sample is deposited on the calibration test strip, no reaction occurs and the color of the calibration test strip should be uniform across the calibration test strip. Thus, the difference in reflection values detected in the first and second images is due to non-uniform illumination.

[0066] In operation 178, each image is preprocessed. The preprocessing can include one or more modifications of each image to enable comparison between images. For example, the preprocessing can include rotating the image and / or cropping the image such that only a portion of the image is utilized in calibration routine 170.

[0067] In operation 182, the "A" matrix is updated with the preprocessed images. In the "A" matrix, the i-th column of "A" is the intensity distribution of the i-th LED powered to an illumination intensity or brightness on the object plane (e.g., the plane corresponding to the top surface of the reagent card). Vignetting V can be calibrated separately. Similarly, A iThe i-th column is the illumination intensity distribution of the i-th LED measured at unit power in the image plane.

[0068] An exemplary "A" matrix can be described in the form of a matrix where P 1×m =V m×m A m×n W 1×n where v is the vignetting function, w is the LED illumination intensity or brightness, m is the number of grid points on the object and image planes, and n is the number of LEDs. To adapt the image plane intensity, the weight w i needs to be determined.

[0069] For a single LED having a radiant intensity distribution given by L(q) placed on the object plane, the irradiance at any point (x,y) on the plane is:

Equation

Equation

[0070] Illumination by one or more LEDs supplied with uniform power tapers at the edges of the object plane which is the image plane and is worsened by vignetting. To obtain a uniform illumination intensity, the LED power is increased for LEDs closer to the edges of the object plane and thus the illumination intensity is increased. In one embodiment, adjusting the power of each LED is performed by using different current limiting resistors and / or pulse width modulation.

[0071] In step 186, for substantially uniform illumination within the image plane, for a given vector, 0 ≦ w ≦ w max subject to the condition that c 1×m and A I =VA minimize(||AI w-c|| 2 +λ||w|| 1 ) The optimization problem is solved. In an alternative embodiment, the optimization can be performed based on the LED current or power rather than the LED illumination intensity, and a constant vector c specifies the total incident power. By solving this optimization problem, it is not necessary to calibrate or model the vignetting separately. Further, by the above selection of c, the optimization problem effectively adapts the illumination intensity to not only uniform illumination but also any function. In one embodiment, updating the "A" matrix by the pre-processed image is executed by the processor 148 and can be stored in the memory 152 or the database 156. The image is then corrected for rotation, segmented, vectorized, and assembled from the "A" matrix. The optimized LED intensities are used to power each of the LEDs 64a - t, and an image is taken again for evaluation. In one embodiment, the LED intensities can be determined by using, for example, the CVX optimization package in MATLAB and the following code: cvx_begin variable w(led.count) minimize(norm(A*w - b)) subject to 0 <= w <= 1 cvx_end

[0072] In operation 190, the LED intensity is compiled into an LED intensity file and stored by processor 148 in memory 152, database 156, or another suitable storage medium, or a combination thereof. The LED intensity file can store LED state data for each of LEDs 64a - t. The LED intensity can be stored in the LED intensity file as a single LED intensity for each of LEDs 64a - n, or as LED intensities for each channel of a desired color model. For example, for each of LEDs 64a - t, or for each channel of an RGB color model or any other desired color model, a red component LED intensity, a green component LED intensity, and a blue component LED intensity can be stored.

[0073] In operation 194, camera 126 can detect a test optical signal indicative of the reflection value of a calibration test strip disposed within sample holder 32, or acquire a test image, with each of LEDs 64a - t enabled for each unique LED state data within the LED intensity file, for example. Camera 126 can detect a test image having a region of pixels having a color or reflection value representative of the color of the calibration test strip and transmit such an image to controller 144.

[0074] In operation 198, controller 144 can evaluate the test image to determine a non - uniformity value. The non - uniformity value can be expressed as a percentage of the non - uniformity of the illumination intensity within the test image. In an exemplary embodiment, the non - uniformity percentage is less than 5%. If the non - uniformity percentage is greater than 5%, controller 144 can make an indication of a failure to successfully complete calibration routine 170, attempt to re - execute calibration routine 170, and / or any combination thereof, or can do nothing.

[0075] Furthermore, as will be understood by those skilled in the art, for example, in order to reduce the downtime for the reagent analyzer 10, the calibration routine 170 can be performed with one or more calibration test strips on the reagent card, and the remaining test strips are used to test the sample as described above. In one embodiment, the reagent analyzer 10 can determine the non-uniformity value before the sample is analyzed to confirm the current calibration. If it is determined that the reagent analyzer 10 is not calibrated, the calibration routine 170 can be executed.

[0076] Next, referring to FIG. 9, there is shown an exemplary embodiment of a reagent analyzer 10a constructed similarly to the reagent analyzer 10 discussed above, but the reagent analyzer 10a has a first polarizer 202a and a second polarizer 202b. Elements common between the reagent analyzer 10 and the reagent analyzer 10a are denoted by the same reference numerals. The first polarizer 202a and the second polarizer 202b can be linear-absorbing (or dichroic) polarizing filters constructed from any suitable material such as, for example, polyvinyl alcohol (PVA), cellulose triacetate (CTA), and combinations thereof.

[0077] The first polarizer 202a can have a first transmission axis 206a, a first boundary 210a, a second boundary 210b located opposite the first boundary 210a, and an aperture 214 (also referred to herein as the second aperture), and can be disposed within the cavity 18 and placed between the circuit board 34 and the sample holder 32, such that light generated by one or more light sources 42a - n is provided to the first boundary 210a, and a portion of the light passes through the first polarizer 202a and the second boundary 210b. In some embodiments, the light generated by one or more light sources 42a - n is provided directly to the first boundary 210a.

[0078] When light is provided to the first boundary 210a, the first polarizer 202a can be configured such that the portion of the light linearly polarized parallel to the first transmission axis 206a is transmitted from the second boundary 210b, and the portion of the light linearly polarized perpendicular to the first transmission axis 206a is absorbed.

[0079] In one embodiment, the first polarizer 202a is attached to the bottom surface 61a of the circuit board 34 to cover one or more illumination sources 42a - n. In another embodiment, the first polarizer 202a is attached within the cavity 18 below the circuit board 34 and above the sample holder 32.

[0080] The second opening 214 can be aligned (i.e., overlapped) with the first opening 38. The second opening 214 can extend from the first boundary 210a to the second boundary 210b and be aligned with the first opening 38 to enable the field of view 40 of the imaging system 22 to proceed from the imaging system 22 through the circuit board 34 and the first polarizer 202a to the sample holder 32, providing a controlled field of view of the test device 44 associated with the sample holder 32 to the camera 26. The second opening 214 can be configured in any shape such that the field of view 40 is the controlled field of view of the sample holder 32 and light generated by one or more illumination sources 42a - n is provided to the first polarizer 202a.

[0081] For example, in some embodiments, the first polarizer 202a includes a plurality of separate polarizers that cover one or more of the one or more illumination sources 42a - n. In this embodiment, the second opening 214 can be formed by eliminating the separate polarizers aligned with the first opening 38.

[0082] The second polarizer 202b can have a second transmission axis 206b, a third boundary 210c, and a fourth boundary 210d, and can be disposed within the cavity 18 and placed between the imaging system 22 and the circuit board 34. Thus, the field of view 40 of the imaging system 22 passes through the second polarizer 202b, and the light reflected from the sample holder 32, the test device 44, and / or the sample 46 is received by the third boundary 210c and advanced through the second polarizer 202b and the fourth boundary 210d to the imaging system 22 and / or the camera 26.

[0083] When light is provided to the third boundary 210c, the second polarizer 202b can be configured such that the portion of the light linearly polarized parallel to the second transmission axis 206b is transmitted from the fourth boundary 210d, and the portion of the light linearly polarized perpendicular to the second transmission axis 206b is absorbed.

[0084] In one embodiment, the second polarizer 202b has a fixed orientation, and thus the second transmission axis 206b is substantially orthogonal to the first transmission axis 206a. However, in another embodiment, the second polarizer 202b is movably (e.g., rotatably) attached to the imaging system 22 and / or the camera 26 so that the orientation of the second transmission axis 206b can be adjusted.

[0085] Next, referring to FIG. 10, there is shown a diagram showing an exploded orthographic view of an exemplary embodiment of a circuit board 34 and a first polarizer 202a. The circuit board 34 is composed of a substrate 60, which has a bottom surface 61a and a top surface 61b, a first opening 38 extending between the bottom surface 61a and the top surface 61b, and one or more illumination sources 42a - n. One or more illumination sources 42a - n can be attached to the bottom surface 61a. The first polarizer 202a is composed of a first boundary 210a and a second boundary 210b, a first transmission axis 206a, and a second opening 214 extending between the first boundary 210a and the second boundary 210b. The second opening 214 is aligned with the first opening 38. The first polarizer 202a can be attached to the bottom surface 61a of the circuit board 34 and can cover one or more illumination sources 42a - n.

[0086] Next, referring to FIG. 11, there is shown a diagram showing that the first polarizer 202a filters the non - polarized light 218 generated by one or more illumination sources 42a - n and directly transmits the polarized light 222 toward a test device 44 having a sample 46. The test device 44 having a sample 46 reflects the polarized light 222 and induces diffuse reflection 226 and specular reflection 230 toward a second polarizer 202b. The second polarizer 202b filters the diffuse reflection 226 and the specular reflection 230 and transmits the polarized light 222 toward a camera 26.

[0087] The first polarizer 202a having the first transmission axis 206a can filter the non - polarized light 218 and directly transmit the polarized light 222 toward the sample 46, and the polarized light 222 is linearly polarized parallel to the first transmission axis 206a. The polarized light 222 can be reflected by the sample 46 to cause diffuse reflection 226 and specular reflection 230.

[0088] The diffuse reflection 226 may not be polarized or may be polarized in a direction different from that of the polarized light 222 (i.e., intersecting the first transmission axis 206a). The specular reflection 230 can be polarized in the same direction as the polarized light 222 (i.e., parallel to the first transmission axis 206a).

[0089] Both the diffuse reflection 226 and the specular reflection 230 are directed toward the second polarizer 202b. The second polarizer 202b can filter the diffuse reflection 226 and the specular reflection 230 and directly transmit the polarized light 222 toward the camera 26, and the polarized light 222 is linearly polarized parallel to the second transmission axis 206b.

[0090] When the angle θ provided between one or more light sources 42a - n and the camera 26 is relatively small (e.g., about 5 degrees), it is particularly important to include the first polarizer 202a and the second polarizer 202b. However, the angle θ can be any angle that enables the reagent analyzer 10a to function according to the present disclosure. For example (but not limited to), the angle θ can be about 10 degrees, about 20 degrees, about 30 degrees, about 40 degrees, about 50 degrees, about 60 degrees, about 70 degrees, about 80 degrees, about 90 degrees, or more, as well as ranges that combine two integers falling between two of the above - mentioned values (i.e., a range such as about 13 degrees to about 87 degrees).

[0091] When unpolarized light 218 is provided to the first polarizer 202a, the polarized light 222 transmitted by the first polarizer 202a is linearly polarized parallel to the first transmission axis 206a,

Number

[0092] When the polarized light 222 is provided to the second polarizer 202b, the light transmitted by the second polarizer 202b is linearly polarized parallel to the second transmission axis 206b, and I 2 =I1 cos 2 having an intensity given by Φ, where Φ is the angle between the polarization of the polarized light 222 and the second transmission axis 206b. As shown in FIG. 11, when the polarization of the polarized light 222 is substantially orthogonal to the second transmission axis 206b (i.e., Φ≒90°), the intensity of the light transmitted by the second polarizer 202b is I 2 =I 1 cos 2 (90°)=0, and the second polarizer 202b transmits none of the polarized light 222.

[0093] In one embodiment, the second transmission axis 206b is substantially orthogonal to the first transmission axis 206a. Thus, the polarization of the specular reflection 230 is substantially orthogonal to the second transmission axis 206b, while the polarization of the diffuse reflection 226 is not orthogonal, thereby preventing the specular reflection 230 while allowing a portion of the diffuse reflection 226 to pass through the second transmission axis 206b. In another embodiment, the second polarizer 202b is movable (e.g., rotatable) so that the orientation of the second transmission axis 206b can be adjusted to absorb more or less of the diffuse reflection 226 and / or the specular reflection 230.

[0094] In some embodiments, the test device 44 includes one or more reagent pads on a reagent card or reagent strip. In some cases, a portion of the sample 46 pools or remains on the surface of the test device 44 (e.g., a reagent pad), causing a specular reflection 230. By incorporating the first polarizer 202a and the second polarizer 202b, the polarized light 222 can be related only to the absorption and scattering of light within the reagent pad of the test device 44, providing an improved reading with respect to the concentration of the analyte.

[0095] The following is a numbered list of non - limiting exemplary embodiments of the inventive concept disclosed herein:

[0096] 1. A method comprising: Placing a wet reagent test device within the field of view of a camera sensor, wherein the field of view of the camera sensor passes through an opening extending between a first major surface and a second major surface of a substrate of a circuit board, a volume of a sample is deposited on the wet reagent test device, and thus, when a target component is present in the sample, a reagent within the wet reagent test device can react with the target component; Illuminating the wet reagent test device with light generated by a plurality of light sources attached to a second major surface of a substrate of a circuit board, wherein a portion of the light is a reflected light signal formed by the light reflecting from a wet reagent test device pad and passing through an opening within the substrate of the circuit board; The method further comprises detecting the reflected light signal by the camera sensor and generating an image of at least a portion of the reagent pad.

[0097] 2. The method according to exemplary embodiment 1, further comprising analyzing the image by a processor executing processor-executable code stored within a non-transitory computer-readable medium to determine the presence or absence of a target component within the sample.

[0098] 3. The method according to exemplary embodiment 2, wherein the processor analyzing the image by executing the processor-executable code is further defined as analyzing pixels within the image with respect to a predetermined color indicative of the presence of a target component within the sample.

[0099] 4. The method according to any one of exemplary embodiments 1 to 3, wherein illuminating the wet reagent test device with light generated by a plurality of light sources further comprises supplying each of the light sources with an amount of electricity at a level calculated such that each light source contributes an amount of illumination calculated to provide controlled illumination at the wet reagent test device.

[0100] 5. The method according to exemplary embodiment 4, wherein the controlled illumination is illumination having a substantially uniform intensity at the wet reagent test device.

[0101] 6. The controlled illumination is the method according to exemplary embodiment 4, which is the intensity designed in the wet reagent test device.

[0102] 7. The substrate has a first surface, a second surface located opposite the first surface, and an intermediate region located between the first surface and the second surface. The first group of light sources is arranged adjacent to the first surface of the substrate, and the second group of light sources is arranged within the intermediate region of the substrate. Illuminating the wet reagent test device with light includes providing a first amount of electricity to the first group of light sources and a second amount of electricity to the second group of light sources, and the first amount of electricity is greater than the second amount of electricity. The method according to any one of exemplary embodiments 4 to 6.

[0103] 8. The first amount of electricity operates the first light source among the first group of light sources at a first brightness, and the second amount of electricity operates the second light source among the second group of light sources at a second brightness. The first brightness is greater than the second brightness. The method according to exemplary embodiment 7.

[0104] 9. The light sources are arranged in a planar relationship. The method according to any one of exemplary embodiments 1 to 8.

[0105] 10. Inducing light to the first boundary of the first polarizer, wherein the first polarizer has a first transmission axis and is configured to transmit the portion of the light polarized in the direction parallel to the first transmission axis from the second boundary of the first polarizer; Inducing the reflected light signal to the third boundary of the second polarizer, wherein the second polarizer has a second transmission axis and is configured to transmit the portion of the reflected light signal polarized in the direction parallel to the second transmission axis from the fourth boundary of the second polarizer further comprising. The method according to any one of exemplary embodiments 1 to 9.

[0106] 11. The second transmission axis of the second polarizer is substantially orthogonal to the first transmission axis of the first polarizer. The method according to exemplary embodiment 10.

[0107] 12. The method according to exemplary embodiment 10, wherein the second polarizer is movably attached to the camera sensor such that the second transmission axis of the second polarizer is adjustable.

[0108] 13. A reagent analyzer comprising: A circuit board having a substrate and a plurality of conductive leads extending on or within the substrate, the substrate having a first major surface and a second major surface, the first major surface being located opposite the second major surface, and the substrate having an opening extending between the first major surface and the second major surface; An imaging system configured to capture an image of a wet reagent test device disposed at a reading position within a field of view that extends through an opening formed within the substrate, the image having a plurality of pixels; A processor configured to receive the image and analyze the pixels of the image to determine the presence or absence of a target component in a sample added to the wet reagent pad.

[0109] 14. The reagent analyzer according to exemplary embodiment 13, wherein the first major surface faces the imaging system and further includes a light source attached to the second major surface of the substrate.

[0110] 15. The light source is a first light source, and the reagent analyzer further includes a second light source and a circuit configured to supply electricity to the first and second light sources, such that the first and second light sources contribute to illuminating the wet reagent test device with a calculated amount to provide controlled illumination.

[0111] 16. The reagent analyzer according to exemplary embodiment 15, wherein the controlled illumination has a substantially uniform intensity.

[0112] 17. The substrate has a first surface, a second surface located opposite the first surface, and an intermediate region located between the first surface and the second surface. The first light source is disposed adjacent to the first surface of the substrate, the second light source is disposed within the intermediate region of the substrate, the circuit is configured to provide a first amount of electricity to the first light source and a second amount of electricity to the second light source, and the first amount of electricity is greater than the second amount of electricity. The reagent analyzer according to exemplary embodiment 15.

[0113] 18. The first amount of electricity operates the first light source at a first brightness, the second amount of electricity operates the second light source at a second brightness, and the first brightness is greater than the second brightness. The reagent analyzer according to exemplary embodiment 17.

[0114] 19. The second main surface of the substrate is planar. The reagent analyzer according to exemplary embodiment 14.

[0115] 20. The opening is a first opening: A first polarizer having a first transmission axis, a first boundary facing the light source such that light generated by the light source is incident on the first boundary, a second boundary facing the wet reagent test device, and a second opening extending between the first boundary and the second boundary, the first polarizer being configured to transmit a portion of the light generated by the light source that is polarized in a direction parallel to the first transmission axis from the second boundary, and the first opening overlapping the second opening; the first polarizer; A second polarizer having a second transmission axis, a third boundary facing the first opening of the substrate such that light reflected by the wet reagent device is incident on the third boundary, and a fourth boundary facing the imaging system, the second polarizer being configured to transmit a portion of the light reflected by the wet reagent device that is polarized in a direction parallel to the second transmission axis from the fourth boundary. The reagent analyzer according to exemplary embodiment 14 further includes the second polarizer.

[0116] 21. The second transmission axis of the second polarizer is substantially orthogonal to the first transmission axis of the first polarizer. The reagent analyzer according to exemplary embodiment 20.

[0117] 22. The second polarizer is the reagent analyzer according to exemplary embodiment 21, which is movably attached to the imaging system so that the second transmission axis of the second polarizer can be adjusted.

[0118] 23. An apparatus comprising: A housing that is opaque to visible light and surrounds a cavity; A camera sensor having a field of view within the cavity; A sample tray disposed within the cavity, having a sample holder within the field of view of the camera sensor and disposed at a distance from the camera sensor; A circuit board disposed between the camera sensor and the sample tray within the cavity, having a substrate and a plurality of conductive leads extending on or within the substrate, the substrate having a first main surface facing the camera sensor and a second main surface facing the sample tray, the first main surface being located opposite to the second main surface, the substrate having an opening extending between the first main surface and the second main surface, the opening being disposed within the field of view of the camera sensor such that the field of view of the camera passes through the opening to provide a controlled field of view of the sample holder of the sample tray to the camera sensor; A light source attached to the second main surface of the substrate and connected to at least a portion of the plurality of conductive leads extending on the substrate; And a circuit configured to be attached to the conductive leads and supply electricity to the light source via the conductive leads.

[0119] 24. The apparatus according to exemplary embodiment 23, wherein the light source includes a plurality of light sources arranged and supported in a planar configuration.

[0120] 25. The apparatus according to exemplary embodiment 24, wherein the second main surface of the substrate is planar.

[0121] 26. The apparatus according to exemplary embodiment 24 or 25, wherein the circuit is configured to supply electricity to each of the light sources such that each light source contributes to the illumination of the sample holder of the sample tray in an amount calculated to provide controlled illumination of the sample holder.

[0122] 27. The controlled illumination is the apparatus according to exemplary embodiment 26, which has a substantially uniform intensity over the range of the sample tray.

[0123] 28. The substrate has a first surface, a second surface located opposite the first surface, and an intermediate region located between the first surface and the second surface. The first group of light sources is arranged adjacent to the first surface of the substrate, the second group of light sources is arranged within the intermediate region of the substrate, the circuit provides a first amount of electricity to the first group of light sources and a second amount of electricity to the second group of light sources, and the first amount of electricity is greater than the second amount of electricity. The apparatus according to exemplary embodiment 24.

[0124] 29. The first amount of electricity operates the first light source among the first group of light sources at a first brightness, the second amount of electricity operates the second light source among the second group of light sources at a second brightness, and the first brightness is greater than the second brightness. The apparatus according to exemplary embodiment 28.

[0125] 30. The sample holder has a first major axis and a first minor axis, and the opening in the substrate has a second major axis parallel to the first major axis. The apparatus according to any one of exemplary embodiments 23 to 29.

[0126] 31. The opening is a first opening: A first polarizer disposed between the light source and the sample tray within the cavity, having a first transmission axis, a first boundary facing the light source such that the light generated by the light source is incident on the first boundary, a second boundary facing the sample tray, and a second opening extending between the first boundary and the second boundary, and configured to transmit the portion of the light generated by the light source that is polarized in a direction parallel to the first transmission axis from the second boundary; A second polarizer attached to the camera sensor, having a second transmission axis, a third boundary facing the first opening of the substrate such that light reflected by the sample tray is incident on the third boundary, and a fourth boundary facing the camera sensor, and configured to transmit, from the fourth boundary, a portion of the light reflected by the sample tray that is polarized in a direction parallel to the second transmission axis; and the apparatus according to any one of exemplary embodiments 23 to 30.

[0127] 32. The apparatus according to exemplary embodiment 31, wherein the second transmission axis of the second polarizer is substantially orthogonal to the first transmission axis of the first polarizer.

[0128] 33. The apparatus according to exemplary embodiment 32, wherein the second polarizer is movably attached to the camera sensor such that the second transmission axis of the second polarizer is adjustable.

[0129] 34. An apparatus comprising: A circuit board having a substrate, the substrate having a first main surface and a second main surface, the first main surface being located opposite to the second main surface, and the first opening extending between the first main surface and the second main surface; A light source attached to the second main surface of the substrate; A first polarizer having a first transmission axis, a first boundary facing the light source, a second boundary facing the first boundary, and a second opening extending between the first boundary and the second boundary, the second opening overlapping the first opening; A camera sensor having a field of view extending through the first opening formed in the substrate and the second opening formed in the first polarizer; A sample tray having a sample holder within the field of view of the camera sensor and disposed at a distance from the camera sensor; And a second polarizer having a second transmission axis substantially orthogonal to the first transmission axis and attached to the camera sensor.

[0130] It should be understood that the steps disclosed herein can be performed simultaneously or in any desired order. For example, one or more of the steps disclosed herein can be omitted, one or more steps can be further divided into one or more sub-steps, and two or more steps or sub-steps can be combined into a single step. Further, in some exemplary embodiments, one or more steps can be repeated one or more times, and such repetitions can be performed sequentially or interspersed with other steps or sub-steps. Additionally, one or more other steps or sub-steps can be performed, for example, before, after, or between the steps disclosed herein.

[0131] Although the inventive concept disclosed herein has been described in relation to detecting the reflectance value of a reagent pad, it should be understood that in some exemplary embodiments of the inventive concept, an absorbance value, a transmittance value, or any other value or property related to the color or change in color of the reagent pad can also be used to calculate the calibration.

[0132] From the above description, it is apparent that the inventive concept disclosed herein is well adapted to carry out these objectives and to achieve the advantages described herein as well as the advantages inherent in the inventive concept disclosed herein. Although exemplary embodiments of the inventive concept disclosed herein have been described for the purposes of this disclosure, numerous modifications readily apparent to those skilled in the art can be made, and such modifications are understood to be within the scope of the inventive concept as disclosed and defined in the appended claims.

Claims

**Claim 1** A method comprising: placing a wet reagent test device within the field of view of a camera sensor, wherein the field of view of the camera sensor passes through an opening extending between a first major surface and a second major surface of a substrate of a circuit board, and the wet reagent test device has a deposited amount of sample such that if a target component is present in the sample, a reagent within the wet reagent test device can react with the target component; illuminating the wet reagent test device with light generated by a plurality of light sources attached to a second major surface of a substrate of a circuit board by supplying each of the light sources with an amount of electricity at a level calculated to contribute to an amount of illumination such that each light source provides controlled illumination at the wet reagent test device; a portion of the light being a reflected light signal formed by the light reflecting from a wet reagent test device pad and passing through an opening within the substrate of the circuit board; detecting the reflected light signal with the camera sensor to generate an image of at least a portion of the reagent pad; directing the light to a first boundary of a first polarizer, the first polarizer having a first transmission axis and being configured to transmit from a second boundary of the first polarizer a portion of the light polarized in a direction parallel to the first transmission axis; directing the reflected light signal to a third boundary of a second polarizer, the second polarizer having a second transmission axis and being configured to transmit from a fourth boundary of the second polarizer a portion of the reflected light signal polarized in a direction parallel to the second transmission axis; the method as described above. **Claim 2** The method of claim 1, further comprising analyzing the image by a processor executing processor-executable code stored in a non-transitory computer-readable medium to determine the presence or absence of a target component in the sample. **Claim 3** The method of claim 2, wherein the processor analyzing the image by executing processor-executable code is further defined as analyzing pixels within the image with respect to a predetermined color indicative of the presence of a target component in the sample. **Claim 4** The method of claim 1, wherein the controlled illumination is illumination having a substantially uniform intensity at the wet reagent test device. **Claim 5** The method of claim 1, wherein the controlled illumination is illumination at a designed intensity at the wet reagent test device. **Claim 6** The substrate has a first surface, a second surface located opposite the first surface, and an intermediate region located between the first surface and the second surface. The first group of light sources is arranged adjacent to the first surface of the substrate, and the second group of light sources is arranged within the intermediate region of the substrate. Illuminating the wet reagent test device with light includes providing a first amount of electricity to the first group of light sources and a second amount of electricity to the second group of light sources, and the first amount of electricity is greater than the second amount of electricity. The method according to any one of claims 1, 4, and 5.

7. The first amount of electricity operates the first light source among the first group of light sources at a first brightness, and the second amount of electricity operates the second light source among the second group of light sources at a second brightness, and the first brightness is greater than the second brightness. The method according to claim 6.

8. The light sources are arranged in a planar relationship. The method according to any one of claims 1 to 7.

9. The second transmission axis of the second polarizer is substantially orthogonal to the first transmission axis of the first polarizer. The method according to claim 1.

10. The second polarizer is movably attached to the camera sensor such that the second transmission axis of the second polarizer is adjustable. The method according to claim 1.

11. A reagent analyzer comprising: A circuit board having a substrate and a plurality of conductive leads extending on or within the substrate, the substrate having a first major surface and a second major surface, the first major surface being located opposite the second major surface, and the substrate having an opening extending between the first major surface and the second major surface. A circuit board; A first light source attached to the second major surface of the substrate; A second light source attached to the second major surface of the substrate; A circuit configured to supply electricity to the first and second light sources so that the first and second light sources contribute to illuminating the wet reagent test device with a calculated amount to provide controlled illumination; An imaging system having a field of view extending through an opening formed in the substrate and configured to capture an image of a wet reagent test device disposed at a reading position within the field of view, the image having a plurality of pixels. An imaging system; A processor configured to receive the image and analyze the pixels of the image to determine the presence or absence of a target component in a sample added to the wet reagent pad; The opening is a first opening: A first polarizer having a first transmission axis, a first boundary facing the light source such that light generated by the light source is incident on the first boundary, a second boundary facing the wet reagent test device, and a second opening extending between the first boundary and the second boundary, configured to transmit a portion of the light generated by the light source polarized in a direction parallel to the first transmission axis from the second boundary, and the first opening overlapping the second opening; A second polarizer having a second transmission axis, a third boundary facing the first opening of the substrate such that light reflected by the wet reagent device is incident on the third boundary, and a fourth boundary facing the imaging system, configured to transmit a portion of the light reflected by the wet reagent device polarized in a direction parallel to the second transmission axis from the fourth boundary; Including the Reagent analyzer.

12. The reagent analyzer according to claim 11, wherein the controlled illumination has a substantially uniform intensity.

13. The substrate has a first surface, a second surface located opposite the first surface, and an intermediate region located between the first surface and the second surface. The first light source is disposed adjacent to the first surface of the substrate, the second light source is disposed within the intermediate region of the substrate, the circuit is configured to provide a first amount of electricity to the first light source and a second amount of electricity to the second light source, and the first amount of electricity is greater than the second amount of electricity. The reagent analyzer according to claim 11.

14. The first amount of electricity operates the first light source at a first brightness, the second amount of electricity operates the second light source at a second brightness, and the first brightness is greater than the second brightness. The reagent analyzer according to claim 13.

15. The reagent analyzer according to claim 11, wherein the second main surface of the substrate is planar.

16. The reagent analyzer according to claim 11, wherein the second transmission axis of the second polarizer is substantially orthogonal to the first transmission axis of the first polarizer.

17. The reagent analyzer according to claim 16, wherein the second polarizer is movably attached to the imaging system such that the second transmission axis of the second polarizer is adjustable.

18. An apparatus comprising: An opaque housing to visible light surrounding the cavity; A camera sensor having a field of view within the cavity; A sample tray disposed within the cavity, having a sample holder within the field of view of the camera sensor and disposed at a distance from the camera sensor; A circuit board disposed between a camera sensor and a sample tray within a cavity, having a substrate and a plurality of conductive leads extending on or within the substrate, the substrate having a first main surface facing the camera sensor and a second main surface facing the sample tray, the first main surface being located opposite to the second main surface, the substrate having an opening extending between the first main surface and the second main surface, the opening being disposed within the field of view of the camera sensor such that the field of view of the camera passes through the opening to provide a controlled field of view of the sample holder of the sample tray to the camera sensor; A plurality of light sources attached to the second main surface of the substrate and connected to at least a portion of the plurality of conductive leads extending on the substrate; A circuit attached to the conductive leads and configured to supply electricity to the light sources via the conductive leads; A circuit configured to supply electricity to each of the light sources such that each light source contributes to the illumination of the sample holder of the sample tray in an amount calculated to provide controlled illumination of the sample holder by the sample tray; The opening is the first opening: A first polarizer disposed between the light source and the sample tray within the cavity, having a first transmission axis, a first boundary facing the light source such that light generated by the light source is incident on the first boundary, a second boundary facing the sample tray, and a second opening extending between the first boundary and the second boundary, and configured to transmit a portion of the light generated by the light source polarized in a direction parallel to the first transmission axis from the second boundary; A second polarizer attached to the camera sensor, having a second transmission axis, a third boundary facing the first opening of the substrate such that light reflected by the sample tray is incident on the third boundary, And a fourth boundary facing the camera sensor, and configured to transmit a portion of the light reflected by the sample tray polarized in a direction parallel to the second transmission axis from the fourth boundary, including the second polarizer; The said device.

19. The device according to claim 18, wherein the plurality of light sources are arranged and supported in a planar configuration.

20. The device according to claim 19, wherein the second main surface of the substrate is planar.

21. The device according to any one of claims 18 to 20, wherein the controlled illumination has a substantially uniform intensity over the range of the sample tray.

22. The substrate has a first surface, a second surface located opposite to the first surface, and an intermediate region located between the first surface and the second surface. The first group of light sources is arranged adjacent to the first surface of the substrate, the second group of light sources is arranged within the intermediate region of the substrate, the circuit provides a first amount of electricity to the first group of light sources and a second amount of electricity to the second group of light sources, and the first amount of electricity is greater than the second amount of electricity. The apparatus according to claim 19.

23. The first amount of electricity operates the first light source among the first group of light sources at a first brightness, the second amount of electricity operates the second light source among the second group of light sources at a second brightness, and the first brightness is greater than the second brightness. The apparatus according to claim 22.

24. The sample holder has a first major axis and a first minor axis, and the opening in the substrate has a second major axis parallel to the first major axis. The apparatus according to any one of claims 18 to 23.

25. The second transmission axis of the second polarizer is substantially orthogonal to the first transmission axis of the first polarizer. The apparatus according to claim 18.

26. The second polarizer is movably attached to the camera sensor such that the second transmission axis of the second polarizer is adjustable. The apparatus according to claim 25.

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