WO2019108390A1

WO2019108390A1 - Systems to measure particle size distribution and related methods

Info

Publication number: WO2019108390A1
Application number: PCT/US2018/060920
Authority: WO
Inventors: Marcin Piotr MICHALSKI
Original assignee: Xinova, LLC
Priority date: 2017-12-01
Filing date: 2018-11-14
Publication date: 2019-06-06

Abstract

Techniques generally described herein include methods, systems, products, devices, and/or apparatuses generally related to measurement of particle size distribution in a medium (e.g., in gas, liquid, or semi-liquid medium). A particle-size-distribution measurement system may include a cell or a container that may secure the medium that contains particles of various sizes therein.

Description

SYSTEMS TO MEASURE PARTICLE SIZE DISTRIBUTION AND RELATED

METHODS

BACKGROUND

[001] Generally, measuring particle size distribution in a medium may provide various useful information about the medium sampled and/or the particles therein. The medium may be a suitable fluid, such as a gas, liquid, or semi-liquid, which may have any suitable particles dispersed or mixed therein. For example, distribution of particle sizes within the medium may facilitate identification of the particle types, facilitate identification levels of pollutants in the medium, facilitate identification percentage of dissolved particles compared to undissolved particles within the medium, etc.

[002] Accordingly, users and manufacturers of food items made from multiple food elements continue to seek improvements thereto.

SUMMARY

[003] Techniques generally described herein include methods, systems, products, devices, and/or apparatuses generally related to measurement of particle size distribution in a medium. For example, a particle- size-distribution measurement system may include a container (e.g., a cell or a chamber) that may secure the medium that contains particles of various sizes therein. For example, producing motion in the medium may produce corresponding motion of the particles responsive thereto, which may facilitate determining the particle size distribution of the particles present in the medium.

[004] At least some examples described herein illustrate systems to measure a size distribution among a plurality of particles. An example system may include a container having a wall, with the container at least partially enclosed. The container may be configured to receive a medium that contains the plurality of particles. Moreover, the described systems may include a wave generator positioned and configured to produce a wave motion of the medium and of the plurality of particles. The systems may also include a light source configured to generate at least one source light. The at least one light source can be positioned to emit the source light toward the plurality of particles. The described systems may further include a light detector positioned and configured to detect light scattered from at least a portion the plurality of particles, and a controller operably coupled to the detector. The controller may be configured to receive one or more signals from the light detector; responsive to the received one or more signals, determine one or more light frequencies of the light scattered from the at least a portion of the plurality of particles; and determine one or more intensities corresponding to the determined one or more light frequencies.

[005] Some examples described herein illustrate methods to measure a size distribution among a plurality of particles in a medium. The described methods include producing motion of the medium and the plurality of particles therein and emitting a source light from a light source toward the plurality of particles. Moreover, the methods may include, at a light detector, detecting light scattered from at least a portion of the plurality of particles, and at a controller, determining intensities of light frequencies among the light scattered from the at least a portion of the plurality of particles. The methods may also include, at the controller, determining a size distribution among the plurality or particles based at least partially on the determined intensities of corresponding light frequencies.

[006] Features from any of the disclosed embodiments may be used in combination with one another, without limitation. In addition, other features and advantages of the present disclosure will become apparent to those of ordinary skill in the art through consideration of the following detailed description and the accompanying drawings.

[007] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

[008] The foregoing and other features of the present disclosure will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. Understanding that these drawings depict only several examples in accordance with the disclosure and are, therefore, not to be considered limiting of its scope, the disclosure will be described with additional specificity and detail through use of the accompanying drawings, in which:

[009] FIG. 1 is a schematic illustration of a particle-size-distribution measurement system with a medium with particles of different sizes;

FIG. 2 is a schematic top view of a particle- size-distribution measurement system; FIG. 3A is a graph of frequency shifts of small and large particles, shown on time vs. frequency-shift coordinate;

FIG. 3B is a graph showing scattering intensity of large and small particles, shown on frequency-shift-amplitude vs. scattering-intensity scale;

FIG. 4 is a schematic side view of a particle-size-distribution measurement system; FIG. 5 is a schematic top view of a particle- size-distribution measurement system; FIG. 6 is an example method to measure a size distribution among a plurality of particles in a medium;

FIG. 7 is a block diagram illustrating an example computer device; and

FIG. 8 is a block diagram illustrating an example computer program product, all arranged in accordance with at least some embodiments of the present disclosure.

DETAILED DESCRIPTION

[010] In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative examples described in the detailed description, drawings, and claims are not meant to be limiting. Other examples may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented herein. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the Figures, may be arranged, substituted, combined, separated, and designed in a wide variety of different configurations, all of which are implicitly contemplated herein.

[Oil] Techniques generally described herein include methods, systems, products, devices, and/or apparatuses generally related to measurement of particle size distribution in a medium (e.g., in gas, liquid, or semi-liquid medium). A particle-size-distribution measurement system may include a cell or a container that may secure the medium that contains particles of various sizes therein. For example, producing motion in the medium may produce corresponding motion of the particles responsive thereto, which may facilitate determining the sizes of the particles present in the medium and the number of particles of each size in the medium for determining the particle size distribution of the particles in the medium. [012] In some examples, the described systems may produce motion or movement of the medium (e.g., periodic or cyclical), which may facilitate measurement of particle size distribution in the medium. For example, particles of different sizes (and of different corresponding masses) may have correspondingly different responses to cyclical motion. Specifically, as the medium moves (in response to one or more forces applied thereon by the particle-size-distribution measurement system), the medium may apply corresponding forces onto the particles; response of the particles to such forces may vary depending on the particle size and/or mass (e.g., as described below in more detail).

[013] Generally, the response of a particle to the driving forces produced thereon by the medium is proportional to the particle’s geometric cross-section and mass (which may be generally related to the geometric cross-section of the particle). For example, particle’s movement (e.g., cyclical or oscillating movement) may vary from one particle to another based on the respective sizes thereof. Moreover, frequency shift of light scattered from the particles (e.g., Doppler frequency shift) is based on the movement of the particles. Hence, for example, the particle-size-distribution measurement system may include a light detector that is positioned and configured to detect the light scattered from the particles in the medium, and a controller operably coupled to the light detector; the controller may correlate detected wavelengths of the scattered light and the corresponding intensities thereof with the corresponding particle sizes and determine relative and/or absolute quantities of such particles sizes within the medium. Hence, for example, the controller may be configured or programmed to determine the distribution of the various particle sizes within the medium. For example, the controller may be configured to correlate a detected range of wavelengths of the scattered light and the corresponding range of intensities thereof with the corresponding average particle sizes and determine relative and/or absolute quantities of such particles sizes within the medium and, consequently, the distribution of the various particle sizes within the medium.

[014] FIG. 1 is a schematic illustration of a particle-size-distribution measurement system

100 with a medium 10 with particles of different sizes, arranged according to at least some examples described herein. The particle-size-distribution measurement system 100 may subject the medium 10 to cyclical or oscillating forces, to facilitate determining the particle size distribution in the medium 10. As described below in more detail, the particle- size- distribution measurement system 100 may include any number of suitable oscillation mechanisms that may be positioned and configured to apply cyclical and/or oscillatory forces onto the medium 10. [015] In at least one example, the forces applied onto the medium 10 may produce a wave like motion or movement of the medium 10 (e.g., as a force wave, such as a pressure wave such as a sound wave, a sub-audible wave, an audible wave, a supra-audible wave, which propagates through the medium 10). The wave is schematically illustrated as sine-like lines, however, it should be understood that force waves are longitudinal waves.

[016] Moreover, as the medium 10 moves (e.g., responsive to the force(s) applied thereon by the particle- size-distribution measurement system 100), the medium 10 may produce driving forces onto the particles therein. In FIG. 1, particles of different sizes are schematically illustrates as particles 20, 21, where the particle 20 is relatively smaller than the particle 21.

[017] It should be appreciated that, generally, particles of the same or similar size may exhibit the same or similar response or movement in response to the driving forces applied thereon by the medium. Hence, for convenience of illustration and description only a single particle of a first size (e.g., the particle 20) and a single particle of a second size (e.g., the particle 21) are illustrated in FIG. 1; the medium 10, however, may include any number of particles therein, which may have any number of sizes. Generally, the particle sizes (e.g., a diameter, length, or other lateral dimension, or longitudinal dimension) may be on the order one or more microns (e.g., 1 pm, 5 pm, 10 pm, 20 pm, 50 pm, 100 pm, etc.) or less than one micron (e.g., 0.001 pm, 0.01 pm, 0.1 pm, 0.5 pm, etc.). For example, the particle sizes can be greater than about 100 nm, greater than about 250 nm, greater than about 1 pm, greater than about 10 pm, less than about 2 pm, less than about 1 pm, or in ranges of about 10 nm to about 1 pm, about 50 nm to about 2.5 pm, 100 nm to about 500 nm, about 250 nm to about 750 nm, about 500 nm to about 1 pm, about 750 pm to about 1.5 pm, about 1 pm to about 2 pm, or about 1.5 pm to about 2.5 pm.

[018] As mentioned above, one or more oscillations may be produced in the medium 10, which may correspondingly generate one or more forces onto the particles 20 and 21. Specifically, the medium may have oscillations or wave-like movement that may have a velocity V and a frequency v (described below in more detail); oscillations of the medium 10 may apply force Fi onto the particle 20 may and a force F₂ onto the particle 21. For example, the force experienced by the particles 20 and 21 may be generally or substantially proportional to the size or geometric cross-sections thereof. Hence, for example, the force F₂ experienced by the particle 21 may be greater than the force Fi that is experienced by the particle 20. [019] As mentioned above, the medium 10 may include numerous particles that may have any number of sizes. Subjecting the medium 10 to cyclical or oscillatory movement (e.g., wave-like movement or motion) may apply different forces onto the particles in the medium 10, and the forces may vary based on the particle size. Moreover, the corresponding forces may produce corresponding movement of the particles based on the respective sizes thereof. Specifically, for example, particles of the same or similar size and/or mass may move collectively.

[020] Generally, the intensity or velocity of the medium 10 may vary from one example to another and/or may be varied manually and/or by the controller (e.g., by operating one or more wave generators, as described below in more detail). It should be noted that the wave velocity in the medium 10 is a function of the medium. Moreover, the waves or wave-like movement of the medium 10 may have any number of suitable amplitudes, frequency, wavelengths, intensities, or combinations thereof, which may vary from one example to another and/or may be varied manually and/or by the controller. For example, wave intensity or velocity may be chosen such that the amplitude and velocity of collective movement is much greater than the amplitude of Brownian motion of the particles (e.g. , of the particles 20 and 21).

[021] As described below in more detail, the particles (e.g., the particles 20 and 21) may be exposed to a light (e.g., to a monochromatic light), while the medium is in wave-like motion. Hence, for example, the particles (e.g., particles 20 and 21) may scatter the monochromatic light in a manner that results in a frequency shift of the scattered light. Moreover, the frequency shift may correspond to and/or may be at least in part based on the motion of the particles. As noted above, the movement or motion of the particles may vary based on the size and/or shape thereof (e.g., particles of the same material may have approximate the same size to weight ratio/density).

[022] The scattering efficiency of the light (e.g., monochromatic light) can depend on the wavelength of the light. In particular, the scattering efficiency of the light increases as the wavelength of the light decreases. As such, the light can be ultraviolet light or visible light. However, many of the particles (e.g., organic particles) absorb ultraviolet light. As such, in an example, the light can include visible light, such as red light, more preferably green light, or more preferably blue light.

[023] In an example, the light scattered by the particles may be received at a light detector that is configured to determine the light frequency and the intensity of the light scattered by the particles. Furthermore, in a controller that may be operably coupled to the light detector; the controller may be configured (e.g., responsive to a configuration control signal) and/or programmed (e.g., by program instructions) to correlate the light detected light frequencies with corresponding particle size. Moreover, the controller may be configured and/or programmed to correlate intensity of the detected light (for each frequency) with the number, weight, percentage, or combinations thereof of one, some, or each of the particle sizes (e.g., by correlation of the detected light frequencies with the particle size, and the light intensity of the corresponding light frequencies with the concentration and/or number of particles in the medium 10). In an example, based at least in part on the determined light frequencies and/or light intensities, the controller may be configured and/or programmed to determine the distribution of particles in the medium 10 (e.g., ratio of the particles 20 to the particles 21, number of the particles 20 and number of the particles 21, concentration of the particles 20 and/or of the particles 21 in the medium 10).

[024] By cyclically moving the medium 10 (e.g. , in a known or predictable wave-like manner), for example, the frequency of scattered light is shifted rather than broadened, and the signal may be strong, since particles of the same and/or similar sizes move in substantially the same way and scatter light in substantially the same way. Hence, the frequency shift (relative to the incident light or light projected onto the particles) may be relatively larger (e.g., compared with the frequency shift due to Brownian motion), which may improve measurement of the frequency shifts. For example, as the particle movement may be collective (for each size of the particles), heterodyne technique may be more suitable than self-referencing employed traditionally in dynamic light scattering (DLS) measurements.

[025] Generally, the particle-size-distribution measurement system 100 may have any number of suitable configurations, where the medium 10 may be moved or subjected to one or more forces that may produce cyclical or wave-like motion of the medium 10 and of the particles therein, and one or more light sources may expose the particles to one or more lights (e.g., one or more monochromatic lights) to produce scattered light therefrom, which may be detected at a light detector, to determine the particle size distribution in the medium 10.

[026] FIG. 2 is a schematic top view of a particle-size-distribution measurement system lOOa, arranged according to at least some examples described herein. The particle- size- distribution measurement system lOOa includes container l lOa (e.g., a chamber or a cell) that is configured to hold or secure a medium (e.g., medium 10 may be secured in the container 1 lOa).

[027] As mentioned above, the medium 10 may be exposed to a light (e.g., monochromatic light) from at least one light source. In the illustrated example, the particle- size-distribution measurement system lOOa includes a light source l20a. Generally, the light source l20a may be any suitable light source. For example, the light source l20a may be or may include a laser or light emitting diode that may generate light of a suitable frequency (e.g., in the visible range, in the UV range, in the IR range, etc.). The laser can be selected to exhibit a coherence length that is greater than a few millimeters (e.g. , greater than 5 mm, about 10 mm to about 30 mm) since the particle-size-distribution measurement system lOOa can use heterodyne techniques to perform measurements. As such, the laser can include a gas laser (e.g., helium/neon lasers) which can exhibit high spatial quality relative to other types of lasers or frequency stabilized semiconductor lasers. Additionally, or alternatively, the light source l20a may include a polychromatic light source and a filter that is together configured to pass a substantially single frequency light therethrough (e.g., such that the light that is emitted onto the medium 10 is a monochromatic light or has a narrow frequency range).

[028] The light source l20a may be positioned and oriented to emit a light beam 30a toward the container 1 lOa. However, it should be noted that, in some examples, one or more optical elements (e.g., a mirror, a diffraction grating, a prism, a lens, optical fibers, collimators, etc.), which can be considered part of the light source l20a, can direct or re direct the light beam 30a toward the container l lOa and the medium 10 therein. As described above, at least a portion of the light beam 30a may enter the medium 10 (e.g., may enter the container llOa) and may be scattered by the particles in the medium 10. In the illustrated example, the particle- size-distribution measurement system lOOa includes a first beam splitter l30a’ that is positioned and oriented relative to the light source l20a in a manner that splits the light beam 30a into two separate beams (e.g., into a first light beam 30a’ and a second light beam 30a”). Examples of the first beam splitter l30a’ includes 1x2 or 2x2 fiber couplers, such as 1x2 or 2x2 fiber couplers exhibiting diverse coupling ratios of 90%: 10% or 99%:l%.

[029] In an example, the first light beam 30a’ may be directed or emitted toward and/or to the container 1 lOa and to the medium 10, such that the particles in the medium 10 scatter the light from the first light beam 30a’ . For example, the container 1 lOa may be made from a material that is at least partially transparent to the first light beam 30a’ or the container llOa may include a window therein that is at least partially transparent to the light beam 30a’. For instance, the container l lOa can include a standard spectroscopic cuvette, such as a four- window cuvette defining a 2 mm or 4 mm gap.

[030] In an example, the container 1 lOa can be disposed in a container holder (not shown).

Examples of the container holder include a cuvette holder or any suitable transducer-fluid coupling. The container holder can include a first window through which the first light beam 30a’ can reach the container 1 lOa. The container holder can include a second window through which scattered light 40a (e.g., the light scattered by the particles in the medium 10, responsive to the exposure of the particles to the light beam 30a’). The second window can be at an angle (e.g., perpendicular angle) relative to the first window. The container holder can also include at least one additional window. Additionally, the container holder can include a beam dump that is configured to absorb any portions of the first light beam 30a or the scattered light 40a that does not exit the container holder via the first or second window. For example, the beam dump can cover any surface of the container holder that does not form part of the first window, the second window, or another window of the container holder. Absorbing the first light beam 30a or the scattered light 40a with the beam dump can prevent reflection of the first light beam 30a or the scattered light 40a since the reflected light can be scattered by the particles in the medium 10 and interfere with the measurements of the particle-size-distribution measurement system lOOa. In an example, the beam dump can include a black painted surface or hole.

[031] In various illustrated examples, the particle-size-distribution measurement system lOOa may include a light detector l40a that is positioned and oriented to receive scattered light 40a (e.g., the light scattered by the particles in the medium 10, responsive to the exposure of the particles to the light beam 30a’). For example, the light detector l40a may comprise a photodetector, such as a photodiode array or other suitable light detector. An example photodetector includes a silicon switchable gain detector, such as a PDA36A-EC photodetector from Thorlabs of Newton, New Jersey. Moreover, the particle-size- distribution measurement system lOOa may be configured such that the light detector l40a receives the light beam 30a” (e.g., as reference light).

[032] In an example, the light detector l40a is positioned to be perpendicular or substantially perpendicular (e.g., 85° to 95°) relative to the first light beam 30a’. In such an example, the light detector l40a is positioned to only detect the scattered light 40a that is scattered at a perpendicular or substantially perpendicular angle relative to the first light beam 30a’. Positioning the light detector l40a to be perpendicular or substantially perpendicular relative to the first light beam 30a’ substantially prevents Doppler broadening caused by multiple scatterings of the scattered light 40a. Substantially preventing the Doppler broadening can improve the accuracy of the measurements made by the particle-sized-distribution measurement system lOOa. In an example, the light detector l40a is positioned at a non-perpendicular angle relative to the first light beam 30a’. In such an example, the scattered light 40a detected by the light detector l40a may exhibit Doppler broadening caused by multiple scatterings of the scattered light 40a.

[033] The second light beam 30a” is directed to bypass the container l lOa and/or the medium 10. For example, the second light beam 30a” may be a reference beam.

[034] The particle-size-distribution measurement system lOOa may include multiple mirrors (e.g., mirror l50a) that are positioned effective to redirect the second light beam 30a” from the first beam splitter l30a’ to the light detector l40a (e.g., via the second beam splitter l30a”). It should be appreciated, however, that the particle-size-distribution measurement system lOOa may include any number of suitable devices and/or mechanism (e.g., prisms, mirrors, lenses, etc.) that are positioned and/or configured to redirect the second light beam 30a” from the first beam splitter l30a’ to the light detector l40a, which may vary from one example to another. The measurement system lOOa can also include mirrors or other suitable devices and/or mechanisms that are positioned and/or configured to redirect the first light beam 30a’ or the scattered light 40a to the container llOa or the light detector l40a, respectively.

[035] The particle-size-distribution measurement system lOOa may include a second beam splitter l30a” that is configured to combine the scattered light 40a and the second light beam 30a” (e.g., the attenuated reference beam 50a). The second beam splitter l30a” can co-linearly combine the scattered light 40a and the second light beam 30a” and cause both the scattered light 40a and the second light beam 30a” to hit the same location of the light detector l40a which can improve the accuracy of the particle-size-distribution measurement system lOOa. Examples of the second beam splitter l30a” includes 1x2 or 2x2 fiber couplers, such as 1x2 or 2x2 fiber couplers exhibiting diverse coupling ratios of 50%:50%, 90%: 10%, or 99%:l%.

[036] The particle-size-distribution measurement system lOOa include optical wave guides (not shown, e.g., optical fibers) that are configured to direct the light beam 30a, the first light beam 30a’, the second light beam 30a” (e.g., the attenuated reference beam 50a), or the scattered light 40a (collectively referred to as emitted light) instead of mirrors. In such an example, the particle-size-distribution measurement system lOOa can include one or more collimators (not shown) that are configured to enable the emitted light to enter or exit the optical wave guide. The focal length of the collimator can depend on whether the collimator is configured to enable the emitted light to enter or exit the optical wave guide. In particular, a first collimator configured to enable the emitted light to enter the optical wave guide can exhibit a longer focal length (e.g., 18 mm) than a second collimator configured to enable the emitted light to exit the optical wave guide. The smaller focal length of the second collimator causes the emitted light emitted by the second collimator to exhibit a finer diameter than the first collimator which concentrates the emitted light.

[037] The scattered light 40a that exits the container 1 lOa can be emitted in a variety of directions. As such, in an example, the particle-size-distribution measurement system lOOa can include a scattered light collector (not shown) that is configured to increase the amount of the scattered light 40a that reaches the light detector l40a. The scattered light collector can include a lens that is configured to focus the scattered light 40a. The scattered light collector can also include a variable iris diagram to limit saturation of the light detector l40a or to enable the scattered light 40a to enter a collimator.

[038] The particle-size-distribution measurement system lOOa may include a controller

200a operably coupled to the light detector l40a and configured to receive one or more signals therefrom. The controller may be configured (e.g., via program instructions or via control signals) to compare the frequency or frequencies of the scattered light (e.g., of scattered light 40a) to the frequency of the source light (e.g., of the light beam 30a”).

[039] Moreover, as mentioned above, the controller 200a may determine the amount and/or percentage of the particles of different sizes based at least partially on the intensity of the scattered light 40a detected at the light detector l40a. In an example, the intensity of the scattered light 40a may be compared to a selected or reduced intensity of the light beam 30a. For example, the particle-size-distribution measurement system lOOa may include an optical attenuator l60a that may be positioned along the path of the first light beam 30a” and may generate an attenuated reference beam 50a that is detected at the light detector l40a. Hence, for example, the controller 200a may be configured (e.g., responsive to a configuration control signal) and/or programmed (e.g., by program instructions) to compare the intensity of the scattered light 40a with a selected or predetermined intensity of the reference beam 50a. In some examples, the intensity of the reference beam 50a may be selected to be similar to the intensity of the scattered light 40a (e.g. , the optical attenuator l60a may be a fixed attenuator selected to produce a selected intensity of the reference beam 50a that is similar to the intensity of the scattered light 40a; the optical attenuator l60a may be a variable attenuator and may be operably coupled to the controller 200a that may increase or decrease attenuation of the light beam 30a” to produce the reference beam 50a that has a similar intensity to the intensity of the scattered light 40a). In an example, the optical attenuator l60a can be selected to produce a selected intensity of the reference beam 50a that is three decibels to about 50 decibels less than the second light beam 30a”.

[040] In an example, the scattered light 40a and the reference light 50a are configured to irradiate different areas of the light detector l40a. In another example, as shown, the particle-size-distribution measurement system lOOa includes a second beam splitter l30a” that is configured to combine the scattered light 40a and the reference light 50a before the scattered light 40a and the reference light 50a reach the light detector l40a. In such an example, the particle-size-distribution measurement system lOOa can include a 1x2 or 2x2 fiber coupler (e.g., exhibiting a coupling ratio of 50%:50%).

[041] As mentioned above, the particle-size-distribution measurement system lOOa may include one or more wave generators that may be configured to induce a wave-like movement of the medium 10 and/or of the particles therein. In the illustrated embodiment, the particle-size-distribution measurement system lOOa includes at least one wave generator, such as wave generators l70a and l70a’, positioned and oriented to emit waves (e.g., a pressure wave such as a sound wave, a sub-audible wave, an audible wave, a supra- audible wave, etc.) that propagate through the medium 10. For example, the wave generators l70a and l70a’ may include sound emitters, such as speakers, transducers, piezoelectric device, etc., may include vibrating devices, etc. The wave generators l70a and l70a’ can be positioned and configured to emit the waves into the container llOa in a direction that is parallel to or substantially parallel to (e.g. , ± 5°) to the first light beam 30a’ which can maximize the Doppler effect. As described below in more detail, the wave generators l70a and l70a’ may be positioned in direct contact with the medium 10. Alternatively, or additionally, the wave generators l70a and l70a’ may be positioned in contact with one or more of the walls that define the container 1 lOa, such that the wall(s) may vibrate and transfer the vibration to the medium 10. Alternatively, or additionally, the wave generators l70a and l70a’ can be spaced from the container l lOa but configured to transfer the waves to the container 1 lOa. For instance, the wave generators l70a and l70a’ directly contact or are incorporated into the container holder and the container holder is configured to transfer the waves to the container 1 lOa.

[042] The wave generator of the particle-size-distribution measurement system lOOa is configured to not obstruct the first light beam 30a. In an example, as shown, the particle- size-distribution measurement system lOOa includes two wave generators l70a and l70a’. The two wave generators l70a and l70a’ can be positioned to form a gap. In such an example, the first light beam 30a’ can pass between the two wave generators l70a and l70a’ and enter the container 1 lOa via the gap. In an example, the particle-size-distribution measurement system lOOa includes a single wave generator that defines a hole therein. In such an example, the first light beam 30a’ can pass through the hole of the single wave generator and enter the container l lOa. In an example, the particle-size-distribution measurement system lOOa includes a single wave generator that does not define a hole therein. In such an example, the single wave generator is positioned to not obstruct the first light beam 30a’, such as positioned adjacent to (e.g., abutting) a surface of the container llOa that is opposite another surface of the container l lOa through which the first light beam 30a’ enters the container llOa.

[043] In an example, at least one of the wave generators l70a and l70a’ includes an ultrasound transducer, such as a high powered ultrasound transducer working at mechanical resonance. For instance, the ultrasound transducer can include a piezoelectric actuator between 2 coupling masses. In an example, the ultrasound transducer can include an amplifier that is configured to increase the power of the ultrasound transducer. In an example, the ultrasound transducer can include or be coupled to a signal generator.

[044] The wave pulses may affect the time signal of the light detector l40a, which may correspond to frequency shifts. Moreover, the frequency shifts may be dynamically dependent on wave phase (e.g., as shown in time vs. frequency shift graph of FIG. 3 A). From the time-dependent frequency shift dynamics, the maxima may be identified, resulting in intensity vs. frequency shift data (e.g., as shown in the frequency shift amplitude vs. scattering intensity graph of FIG. 3B). The phase of frequency shifts relative to the phase of the wave may be different for relatively small and large particles as illustrated, because the relatively large particles may be more inert (e.g., producing a smaller frequency shift).

[045] As frequency shifts may correspond, be correlated, or be related to particle sizes

(e.g., a range of particle sizes may be mapped to an average particle size within some defined tolerance), and intensity of the scattered light of specific frequencies may correspond, be correlated, or be related to the number of particles that scatter the light (e.g., an average density may be mapped to an average number of particles within some defined tolerance), the particle size distribution may be determined by the controller 200a. Furthermore, intensity and/or frequency of the wave advancing through the medium 10 may be varied (e.g., between measurements), which may improve accuracy and/or increase resolution of the determined size distribution of particles.

[046] Generally, the controller 200a may be configured and/or programmed in any number of suitable ways to determine the frequency shifts and/or correlate the frequency shifts with the particle sizes and/or correlate the corresponding light intensities with the number of particles, which enables determining a size distribution of the particles. For example, the controller 200a may include and/or may be operably coupled to a table that includes data to correlate the frequency shifts with the particle sizes and the intensities with the number of particles (e.g., the value in the table may be empirically determined, such as by iterative testing known particle size distributions, and/or may be calculated) to determine the particle size distribution. For example, the controller 200a may include and/or may be operably coupled to a table that includes data to correlate a range of frequency shifts with an average particle size and a range of intensities with an average number of particles to determine the particle size distribution. Additionally, or alternatively, the controller 200a may follow and/or execute one or more algorithms to determine the correlation between the frequency shifts and the particle sizes and/or between the intensities with the number of particles and/or to prepare or populate a table.

[047] A particle with radius R that is suspended in a medium (e.g., in liquid, semi-liquid, gas), may undergo movement caused by the movement of the medium and/or by wave imparted on the particle and/or onto the medium. For example, as discussed previously, the wave may be a force wave, such as a pressure wave e.g., a sound wave, a sub-audible wave, an audible wave, a supra-audible wave that propagates through the medium 10. An amplitude of the particle movement may be generally much smaller than the wave-length of the motion wave advancing through the medium, such that the driving force can be predominately time dependent, instead of position dependent.

[048] Consider sound wave propagating along x-direction in fluid, the longitudinal displacement is a specific solution:

Eq. 1: xi =— A_t cos Mi t),

with

Ai: displacement amplitude

coi: angular frequency of the sound wave, coi = 2 p f.

[049] The fluid velocity is given by time derivative:

Eq. 2: V_t = A_tMt sin(M_t t),

44 [050] The particle in a moving liquid experiences force proportional to relative velocity, according to Stokes’ law:

Eq. 3: F = 6pmϋ(n_i - V ),

with

R: sphere radius,

m: fluid viscosity,

V : particle velocity,

Vi: local fluid velocity.

[051] The equation is valid as long as the flow around the particle is laminar. In order to get the impression of velocity region, where the assumption is valid, Reynolds number Re [2] is considered:

2 R pi AV

Eq. 4: Re =

m

[052] The characteristic length scale is particle diameter (2R), and purely laminar flow exists up to Re = 10. Resolving for DU_{hΐ ic} in water:

AV_max(50 nm) = 100 m/s, AV_maX(2.5 pm) = 2 m/s.

[053] These velocities exceed typical Brownian motion mean velocities (cm/s range).

Starting from the force formula in Eq. 3, motion differential equation is:

Eq. 6: mx = 6pmH(Ai<ύi sin (w_¾ · t)— x),

Eq. 7: mx + 6pmHc = 6pmHAi< i sin(w_¾ · t).

[054] With the mass of spherical particle m = 4/3 · p · R³ · p we get

[055] This second-order differential equation can be rewritten as set of two first-order equations for the purpose of numerical solving. Substituting x₁ = x and x₁ = x we get

[056] In some examples, the wave frequency and/or wave intensity may be selected to minimize and/or avoid breaking-up or damaging the particles. For example, moderate intensity waves may be suitable to accelerate the particles without damaging and/or breaking up the particles. Moreover, the particle-size-distribution measurement system lOOa may be configured to determine or test particle sensitivity to the waves (e.g., how susceptible the particles are to breakup responsive to the waves acting thereon). For example, the medium 10 and the particles may be first exposed to low intensity waves, and the particle size distribution may be determined during such exposure. Subsequently, the medium 10 and the particles may be exposed to high intensity waves, and the particle size distribution may be determined during such exposure. Finally, medium 10 and the particles may be exposed again to the low intensity wavers, and the particle size distribution may be determined during such exposure. The controller may be configured and/or programmed to compare the size distribution determined under both low intensity waves exposures (e.g. , if the controller determines more relatively smaller-sized particles under second low intensity waves exposure than under the first low intensity waves exposure, the controller may determine that the particles are sensitive to damage and/or breakup when exposed to at least the high intensity waves).

[057] The position and velocity amplitudes of the particles are different than the position and velocity amplitudes of the medium 10 and the movement of the particles is delayed relative to the movement of the medium 10. The particle-size-distribution measurement system lOOa can detect the maximum velocity and the phase difference ratios between the particles and the medium 10. The controller 200a can be configured to analyze the maximum velocity and phase difference ratios to determine the particle size of the particles. The accuracy of the particle-size-distribution measurement system lOOa can be improved by causing the maximum velocity ratio to be noticeably less than one (e.g. , less than 0.99, less than 0.95, less than 0.9, less than 0.8, less than 0.7) and the phase difference ratio to be noticeably greater than zero (e.g., greater than 0.01, greater than 0.05, greater than 0.1, greater than 0.2, or greater than 0.3). The maximum velocity and phase difference ratios depends on the particle size of the particles and the frequency of the wave emitted by the wave generators l70a and l70a’. As such, the frequency of the waves emitted by the wave generators l70a and l70a’ can be selected to cause the maximum velocity ration to be noticeably less than one or the phase difference ratio to be noticeably greater than zero for selected particle sizes. It is noted that the maximum velocity and phase difference ratios can be independent of the wave intensity.

[058] For example, the frequency of the waves emitted by the wave generators l70a and l70a’ can be about 100 kHz to about 300 kHz when the particle size of the particles is about 50 nm to about 2.5 pm (e.g., about 100 nm to about 2.5 pm, about 250 nm to about 1 pm, or about 500 nm to about 1.5 pm). In such an example, the frequency of the waves can be about 100 kHz to about 150 kHz, about 125 kHz to about 175 kHz, about 150 kHz to about 200 kHz, about 175 kHz to about 225 kHz, about 200 kHz to about 250 kHz, about 225 kHz to about 275 kHz, or about 250 kHz to about 300 kHz. In an example, the frequency of the waves emitted by the wave generators l70a and l70a’ can be greater than about 300 kHz when the particle size of the particles is less than about 500 nm (e.g. , less than 250 nm, less than 100 nm, or less than 50 nm). In such an example, the frequency of the waves emitted by the wave generator can be greater than about 500 kHz or greater than about 1 MHz. It is noted that the maximum velocity and phase difference ratios for particles larger than about 1 pm (e.g., larger than 2 pm, larger than 3 pm) can become saturated at frequencies that are greater than about 300 kHz thereby diminishing the accuracy of the particle-size-distribution measurement system lOOa. In another example, the frequency of the wave emitted by the wave generators l70a and l70a’ can be less than about 100 kHz when the particle size of the particles is greater 1 pm (e.g. , greater than 1.5 pm, greater than about 2 pm, or greater than about 2.5 pm). In such an example, the frequency of the waves emitted by the wave generators l70a and l70a’ can be less than about 50 kHz or less than 30 kHz. It is noted that the maximum velocity and phase difference ratios for particles smaller than about 750nm (e.g., less than about 500 nm, less than about 250 nm, less than about 100 nm, less than about 50 nm) are about one and zero, respectively, at frequencies that are less than about 100 kHz.

[059] As described above, the source light may be split into two beams, one of which may be directed to the light detector, while bypassing the medium (e.g., to provide a reference light). Alternatively, the particle-size-distribution measurement system may include multiple light sources that are configured to emit light of substantially the same wavelength (e.g., the same wavelength monochromatic light).

[060] FIG. 4 is a schematic side view of a particle-size-distribution measurement system lOOb, arranged according to various examples described herein. In the illustrated example, the particle- size-distribution measurement system lOOb includes a wave generator l70b positioned inside the container l lOb. For example, the wave generator l70b (e.g., a speaker, a transducer, a piezoelectric device, etc.) may generate cyclical vibrations in the medium 10 (e.g., via direct contact therewith).

[061] Moreover, the wave generator l70b may be operably coupled to a controller 200b.

For example, as described herein, the controller 200b may control the operation of the wave generator l70b. In an example, the controller 200b may direct the wave generator l70b to increase or decrease wavelength of the motion of the medium 10. Similarly, the controller 200b may direct the wave generator l70b to increase or decrease the intensity of the wavelengths of the motion of the medium 10. [062] FIG. 5 is a schematic side view of the particle-size-distribution measurement system lOOc, arranged according to at least one example described herein. As shown in FIG. 5, particle-size-distribution measurement system lOOc may include a wave generator l70c that is positioned outside of the container 1 lOc. The wave generator l70c may be positioned such as to transfer energy to one or more walls of the container llOc, which in turn may transfer the energy to the medium 10, thereby producing a wave-like motion thereof. Generally, the container llOc may include any number of suitable materials (e.g., suitable rigid materials) that may transfer vibrations from the wave generator l70c to the medium 10. For example, the walls of the container 1 lOc may be comprised of glass, metal, plastic, combinations of materials, etc.

[063] In an example, the container 1 lOc includes a controller 200c operably coupled to the wave generator l70c. For example, as described herein, the controller 200c may control the operation of the wave generator l70c. In an example, the controller 200c may direct the wave generator 170c to increase or decrease wavelength of the motion of the medium 10. Similarly, the controller 200c may direct the wave generator l70c to increase or decrease the intensity of the wave advancing through the medium 10.

[064] In an example, as shown, the wave generator l70c is directly coupled to the container llOc. In another example, the wave generator l70c can be spaced from but coupled to the container 1 lOc such that at least some of the wave generated by the wave generator l70c reach the container l lOc. For instance, the measurement system lOOc can include a transducer coupling mass (e.g. , a cuvette holder) and the wave generator l70c can include an ultrasonic transducer that is disposed in or coupled to the transducer coupling mass. The transducer coupling mass can be configured to hold the container l lOc (e.g., hold a cuvette). The transducer coupling mass can then transmit vibrations from the ultrasonic transducer to the container 1 lOc.

[065] It should be also appreciated that any number of suitable mechanisms may be included in the particle-size-distribution measurement system and/or coupled thereto for generating cyclical and/or wave-like motion of the medium. For example, the container may be alternating moved or shaken to produce wave-like motion of the medium therein (e.g., of a liquid therein). Additionally, or alternatively, a movable element (e.g., a piston) may be cyclically moved (e.g., reciprocated) in the medium to produce the wave-like motion thereof.

[066] The container 1 lOc exhibits a length measured parallel to the wave propagation.

The length of the container llOc can determine whether the waves generated by the wave generator l70c forms propagating waves, standing waves, or local movement of the medium 10. For example, the length of the container llOc can be configured to form propagating waves when the length of the container 1 lOc is at, near, or greater than the wavelength of the waves. In such an example, a surface of the container 1 lOc opposite the wave generator l70c includes a wave absorber to prevent reflection of the waves (wave reflection would create deconstructive or constructive interference). In an example, the length of the container 1 lOc matches the resonance frequency of the wave thereby creating standing waves. It is noted that standing waves may create particle segregation which can inhibit concentration measurements. In another example, the length of the container llOc is significantly less than the wavelength of the waves which results in local movement of the medium 10. Local movement of the medium 10 includes collective medium 10 movement without wave formation. The volume of the medium 10 in the container llOc that exhibits a length that is significantly less than the wavelength of the waves requires a smaller volume of the medium 10 than the other containers l lOd. It is noted that the container 1 lOb of FIG. 4 can be configured to form propagating waves, standing waves, or local movement exhibit that the thickness of the wave generator l70b. However, the length of the container 1 lOb may need to be increased to compensate for the thickness of the wave generator l70b.

[067] FIG. 6 is an example method 220 to measure a size distribution among a plurality of particles in a medium, according to some examples. The example method 220 may include one or more operations, functions or actions as illustrated by one or more of blocks 225, 230, 235, 240, and/or 245. The operations described in the blocks 225, 230, 235, 240, and/or 245 may be performed in response to execution (such as by one or more processors described herein) of computer-executable instructions stored in a computer-readable medium, such as a computer-readable medium of a computing device or some other controller similarly configured.

[068] An example process may begin with block 225, which recites“producing motion of the medium and the plurality of particles therein.” Block 225 may be followed by block 230, which recites“emitting a source light from a light source toward the plurality of particles.” Block 230 may be followed by block 235, which recites“at a light detector, detecting light scattered from the plurality of particles.” Block 235 may be followed by block 240, which recites“at a controller, determining intensities of light frequencies among the light scattered from the plurality of particles.” Block 240 may be followed by block 245, which recites“at the controller, determining a size distribution among the plurality or particles based at least partially on the determined intensities of corresponding light frequencies.”

[069] The blocks included in the described example methods are for illustration purposes.

In some embodiments, the blocks may be performed in a different order. In some other embodiments, various blocks may be eliminated. In still other embodiments, various blocks may be divided into additional blocks, supplemented with other blocks, or combined together into fewer blocks. Other variations of these specific blocks are contemplated, including changes in the order of the blocks, changes in the content of the blocks being split or combined into other blocks, etc.

[070] Block 225 recites“producing motion of the medium and the plurality of particles therein.” In an example, block 225 includes producing an oscillating motion of the medium and of the plurality of particles therein. In an example, block 225 can include propagating a wave through the medium. In an example, block 225 can include moving a container that holds the medium and the plurality of particles.

[071] Block 230 recites“emitting a source light from a light source toward the plurality of particles.” In an example, block 230 can include emitting a monochromatic source light from the light source toward the plurality of particles.

[072] Block 240 recites,“at a controller, determining intensities of light frequencies among the light scattered from the plurality of particles.” In an example, block 240 includes at the controller, determining a range of intensities of light frequencies among the light scattered from the plurality of particles.

[073] Block 245 recites,“at the controller, determining a size distribution among the plurality or particles based at least partially on the determined intensities of corresponding light frequencies.” In an example, block 245 can include correlating light frequencies with corresponding particle sizes of the plurality of particles and correlating light intensities with the number of particles. In an example, block 245 can include correlating a range of or an average light frequencies with a range of corresponding particle sizes or average particle sizes of the plurality of particles and correlating a range or average light intensities with a range of or an average number of particles.

[074] The method 220 can include exposing the light detector to a reference source light that did not scatter from the plurality of particles, wherein the source light is a monochromatic light, and the reference source light is a monochromatic light of the same frequency as the source light. In an example, exposing the plurality of particles to the source light from the light source and exposing the light detector to the reference source light can include generating the monochromatic light of the reference source light and the monochromatic light of the source light from a single light source. In an example, exposing the plurality of particles to the source light from the light source and exposing the light detector to the reference source light can include generating the monochromatic light of the reference source light and the monochromatic light of the source light from multiple light sources. In some examples, the monochromatic light of the reference source light and the source light have substantially the same intensity. In an example, the method 220 includes at least one of splitting, reflecting, or attenuating the monochromatic from the single light source to produce the reference source light.

[075] FIG. 7 is a block diagram illustrating an example computer device 300 arranged in accordance with at least some examples described herein. According to the illustrated example, the computer device 300 is arranged for at least partially controlling any of the systems disclosed herein in accordance with the present disclosure. For example, the controllers 200a-200d may be configured as the computer device 300. In a very basic configuration 301, computer device 300 typically includes one or more processors 310 and system memory 320. A memory bus 330 may be used for communicating between the processor 310 and the system memory 320.

[076] Depending on the desired configuration, processor 310 may be of any type including but not limited to a microprocessor (mR), a microcontroller (pC), a digital signal processor (DSP), or any combination thereof. Processor 310 may include one or more levels of caching, such as a level one cache 311 and a level two cache 312, a processor core 313, and registers 314. An example processor core 313 may include an arithmetic logic unit (ALU), a floating-point unit (FPU), a digital signal processing core (DSP Core), or any combination thereof. An example memory controller 315 may also be used with the processor 310, or in some implementations, the memory controller 315 may be an internal part of the processor 310.

[077] Depending on the desired configuration, the system memory 320 may be of any type including but not limited to volatile memory (such as RAM), non-volatile memory (such as ROM, flash memory, etc.) or any combination thereof. System memory 320 may include an operating system 321, one or more applications 322, and program data 324. Application 322 may include at least one procedure 323, such as a procedure that controls operating any of the systems disclosed herein (as described above) or the method 220 of FIG. 6. Program data 324 may include instructions for directing receiving one or more signals from the light detector, identifying frequency shifts and corresponding light or signal intensities based on the signals received from the light detector, and determining particle size distribution based on the signals received from the light detector and/or based on the identified frequency shifts and/or light or signal intensities. This described basic configuration is illustrated in FIG. 8 by those components within dashed line of the basic configuration 301.

[078] Computer device 300 may have additional features or functionality, and additional interfaces to facilitate communications between the basic configuration 301 and any required devices and interfaces. For example, a bus/interface controller 340 may be used to facilitate communications between the basic configuration 301 and one or more storage devices 350 via a storage interface bus 341. The storage devices 350 may be removable storage devices 351, non-removable storage devices 352, or a combination thereof. Examples of removable storage and non-removable storage devices include magnetic disk devices such as flexible disk drives and hard-disk drives (HDD), optical disk drives such as compact disk (CD) drives or digital versatile disk (DVD) drives, solid state drives (SSD), and tape drives to name a few. Example computer storage media may include volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information, such as computer readable instructions, data structures, program modules, or other data.

[079] System memory 320, removable storage 351 and non-removable storage 352 are all examples of computer storage media. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which may be used to store the desired information and which may be accessed by computer device 300. Any such computer storage media may be part of computer device 300.

[080] Computer device 300 may also include an interface bus 342 for facilitating communication from various interface devices (e.g., output interfaces, peripheral interfaces, and communication interfaces) to the basic configuration 301 via the bus/interface controller 340. Example output devices 360 include a graphics processing unit 361 and an audio processing unit 362, which may be configured to communicate to various external devices such as a display or speakers via one or more A/V ports 363. Example peripheral interfaces 370 include a serial interface controller 371 or a parallel interface controller 372, which may be configured to communicate with external devices such as input devices (e.g., keyboard, mouse, pen, voice input device, touch input device, etc.) or other peripheral devices (e.g., printer, scanner, etc.) via one or more I/O ports 373. An example communication device 380 includes a network controller 381, which may be arranged to facilitate communications with one or more other computer devices 390 over a network communication link via one or more communication ports 382.

[081] The network communication link may be one example of a communication media.

Communication media may typically be embodied by computer readable instructions, data structures, program modules, or other data in a modulated data signal, such as a carrier wave or other transport mechanism, and may include any information delivery media. A “modulated data signal” may be a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, communication media may include wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, radio frequency (RF), microwave, infrared (IR) and other wireless media. The term computer readable media as used herein may include both storage media and communication media.

[082] Computer device 300 may be implemented as a portion of a small-form factor portable (or mobile) electronic device such as a cell phone, a personal data assistant (PDA), a personal media player device, a wireless web-watch device, a personal headset device, an application specific device, or a hybrid device that include any of the above functions. Computer device 300 may also be implemented as a personal computer including both laptop computer and non-laptop computer configurations.

FIG. 8 is a block diagram illustrating an example computer program product 800 that is arranged to store instructions for controlling any of the systems disclosed herein. The signal bearing medium 802 which may be implemented as or include a computer- readable medium 806, a computer recordable medium 808, a computer communication medium 810, or combinations thereof, stores programming instructions 804 that may configure the processing unit to perform all or some of the processes previously described. These instructions may include, for example, one or more executable instructions for receiving one or more signals from the light detector. Moreover, the instruction may include instructions to determine intensities of light frequencies among the light scattered from the plurality of particles, and determine a size distribution among the plurality or particles based at least partially on the determined intensities of corresponding light frequencies.

[083] The present disclosure is not to be limited in terms of the particular examples described in this application, which are intended as illustrations of various aspects. Many modifications and examples can be made without departing from its spirit and scope, as will be apparent to those skilled in the art. Functionally equivalent methods and apparatuses within the scope of the disclosure, in addition to those enumerated herein, will be apparent to those skilled in the art from the foregoing descriptions. Such modifications and examples are intended to fall within the scope of the appended claims. The present disclosure is to be limited only by the terms of the appended claims, along with the full scope of equivalents to which such claims are entitled. It is to be understood that this disclosure is not limited to particular methods, shapes, materials, or compositions which can, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular examples only, and is not intended to be limiting.

[084] With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

[085] It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as“open” terms (e.g., the term“including” should be interpreted as“including but not limited to,” the term“having” should be interpreted as“having at least,” the term “includes” should be interpreted as“includes but is not limited to,” etc.).

[086] It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases“at least one” and“one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles“a” or“an” limits any particular claim containing such introduced claim recitation to examples containing only one such recitation, even when the same claim includes the introductory phrases“one or more” or“at least one” and indefinite articles such as“a” or“an” (e.g.,“a” and/or“an” should be interpreted to mean“at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should be interpreted to mean at least the recited number (e.g. , the bare recitation of“two recitations,” without other modifiers, means at least two recitations, or two or more recitations). [087] Furthermore, in those instances where a convention analogous to“at least one of A,

B, and C, etc.” is used, in general, such a construction is intended in the sense one having skill in the art would understand the convention (e.g.,“a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to“at least one of A, B, or C, etc.” is used, in general, such a construction is intended in the sense one having skill in the art would understand the convention (e.g. ,“a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase“A or B” will be understood to include the possibilities of“A” or“B” or“A and B.”

[088] In addition, where features or aspects of the disclosure are described in terms of

Markush groups, those skilled in the art will recognize that the disclosure is also thereby described in terms of any individual member or subgroup of members of the Markush group.

[089] As will be understood by one skilled in the art, for any and all purposes, such as in terms of providing a written description, all ranges disclosed herein also encompass any and all possible subranges and combinations of subranges thereof. Any listed range can be easily recognized as sufficiently describing and enabling the same range being broken down into at least equal halves, thirds, quarters, fifths, tenths, etc. As a non-limiting example, each range discussed herein can be readily broken down into a lower third, middle third and upper third, etc. As will also be understood by one skilled in the art all language such as“up to,”“at least,”“greater than,”“less than,” and the like include the number recited and refer to ranges which can be subsequently broken down into subranges as discussed above. Finally, as will be understood by one skilled in the art, a range includes each individual member. Thus, for example, a group having 1-3 items refers to groups having 1, 2, or 3 items. Similarly, a group having 1-5 items refers to groups having 1, 2, 3, 4, or 5 items, and so forth.

[090] While the foregoing detailed description has set forth various examples of the devices and/or processes via the use of block diagrams, flowcharts, and/or examples, such block diagrams, flowcharts, and/or examples contain one or more functions and/or operations, it will be understood by those within the art that each function and/or operation within such block diagrams, flowcharts, or examples can be implemented, individually and/or collectively, by a wide range of hardware, software, firmware, or virtually any combination thereof. In one example, several portions of the subject matter described herein may be implemented via Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs), digital signal processors (DSPs), or other integrated formats. However, those skilled in the art will recognize that some aspects of the examples disclosed herein, in whole or in part, can be equivalently implemented in integrated circuits, as one or more computer programs running on one or more computers (e.g. , as one or more programs running on one or more computer systems), as one or more programs running on one or more processors (e.g., as one or more programs running on one or more microprocessors), as firmware, or as virtually any combination thereof, and that designing the circuitry and/or writing the code for the software and/or firmware would be well within the skill of one of skill in the art in light of this disclosure. For example, if a user determines that speed and accuracy are paramount, the user may opt for a mainly hardware and/or firmware vehicle; if flexibility is paramount, the user may opt for a mainly software implementation; or, yet again alternatively, the user may opt for some combination of hardware, software, and/or firmware.

[091] In addition, those skilled in the art will appreciate that the mechanisms of the subject matter described herein are capable of being distributed as a program product in a variety of forms, and that an illustrative example of the subject matter described herein applies regardless of the particular type of signal bearing medium used to actually carry out the distribution. Examples of a signal bearing medium include, but are not limited to, the following: a recordable type medium such as a floppy disk, a hard disk drive (HDD), a Compact Disc (CD), a Digital Video Disk (DVD), a digital tape, a computer memory, etc.; and a transmission type medium such as a digital and/or an analog communication medium (e.g., a fiber optic cable, a waveguide, a wired communication link, a wireless communication link, etc.).

[092] Those skilled in the art will recognize that it is common within the art to describe devices and/or processes in the fashion set forth herein, and thereafter use engineering practices to integrate such described devices and/or processes into data processing systems. That is, at least a portion of the devices and/or processes described herein can be integrated into a data processing system via a reasonable amount of experimentation. Those having skill in the art will recognize that a typical data processing system generally includes one or more of a system unit housing, a video display device, a memory such as volatile and non-volatile memory, processors such as microprocessors and digital signal processors, computational entities such as operating systems, drivers, graphical user interfaces, and applications programs, one or more interaction devices, such as a touch pad or screen, and/or control systems including feedback loops and control motors (e.g., feedback for sensing position and/or velocity; control motors for moving and/or adjusting components and/or quantities). A typical data processing system may be implemented utilizing any suitable commercially available components, such as those typically found in data computing/communication and/or network computing/communication systems.

[093] The herein described subject matter sometimes illustrates different components contained within, or connected with, different other components. It is to be understood that such depicted architectures are merely examples, and that in fact many other architectures can be implemented which achieve the same functionality. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively "associated" such that the desired functionality is achieved. Hence, any two components herein combined to achieve a particular functionality can be seen as "associated with" each other such that the desired functionality is achieved, irrespective of architectures or intermedial components. Likewise, any two components so associated can also be viewed as being "operably connected", or "operably coupled", to each other to achieve the desired functionality, and any two components capable of being so associated can also be viewed as being "operably couplable", to each other to achieve the desired functionality. Specific examples of operably couplable include but are not limited to physically mateable and/or physically interacting components and/or wirelessly interactable and/or wirelessly interacting components and/or logically interacting and/or logically interactable components.

[094] While various aspects and examples have been disclosed herein, other aspects and examples will be apparent to those skilled in the art. The various aspects and examples disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

Claims

1. A system to measure a size distribution among a plurality of particles in a medium, the system comprising:

a container including a wall, wherein the container is at least partially enclosed, and wherein the container is configured to receive the medium that contains the plurality of particles;

a wave generator positioned and configured to produce a wave motion of the medium and of the plurality of particles;

a light source configured to generate a source light, wherein the light source is positioned to emit the source light towards the plurality of particles;

a light detector positioned and configured to detect light scattered from at least a portion of the plurality of particles; and

a controller operably coupled to the light detector and configured to:

recieve one or more signals from the light detector; and

responsive to the received one or more signals, determine one or more light frequencies of the light scattered from the portion of the plurality of particles, and determine one or more intensities corresponding to the determined one or more light frequencies.

2. The system of claim 1, wherein the controller is configured to determine a size distribution among the plurality of particles at least partially based on the determined one or more intensities of the corresponding one or more light frequencies.

3. The system of claim 1, wherein the controller is configured to determine particle sizes of the plurality of particles at least partially based on a frequency shift between a frequency of the at least one source light and a frequency of the detected light that is scattered from the at least a portion of the plurality of particles.

4. The system of claim 1, wherein the controller is configured to:

correlate a first frequency of a first intensity with a first number of particles of a first size; and

correlate a second frequency of a second, higher intensity with a second, greater number of particles of a second size.

5. The system of claim 1, wherein the controller is configured to: correlate a first frequency range of a first intensity range with a first average number of particles of a first average size; and

correlate a second frequency range of a second, higher intensity range with a second, greater number of average particles of a second average size.

6. The system of claim 1, wherein the wave generator is configured to generate a wave that propagates within the medium.

7. The system of claim 1, wherein the wave generator comprises at least one of a speaker, a transducer, or a piezoelectric device.

8. The system of claim 7, wherein the wave generator comprises an ultrasonic transducer.

9. The system of claim 1, wherein the wave generator is operably coupled to the controller, and wherein the controller is configured to direct the wave generator to generate the wave of a selected average frequency.

10. The system of claim 1, wherein the wave generator is configured to generate the wave of a selected average frequency of about 100 kHz to about 300 kHz.

11. The system of claim 1, wherein the wave generator comprises one or more moveable elements configured to produce the wave motion of the medium and of the plurality of particles.

12. The system of claim 1, wherein the wave generator is configured to move a movable body within the medium to produce the wave motion of the medium and of the plurality of particles.

13. The system of claim 1, wherein the wave generator is configured to move or deform the wall.

14. The system of claim 13, wherein the wave generator is configured to produce vibration of the wall.

15. The system of claim 1, wherein the light source is configured to generate monochromatic light.

16. The system of claim 1, wherein the light source comprises a polychromatic light source and a filter, the polychromatic light source and filter are together configured to pass a substantially single frequency light therethrough.

17. The system of claim 1, wherein the light source comprises a laser.

18. The system of claim 1, wherein the laser exhibits a coherence length that is greater than about 5 mm.

19. The system of claim 1, wherein the light source comprises a light emitting diode.

20. The system of claim 1, wherein the light source emits a red light, a blue light, or a green light.

21. The system of claim 1, wherein the light source and the light detector are positioned and configured such that a first portion of the source light is directed to the light detector as a reference light, bypassing the plurality of particles, and a second portion of the source light is directed to the light detector as the light scattered from the portion of the plurality of particles.

22. The system of claim 21, further comprising a beam splitter positioned to direct the first portion of the source light to the light detector as reference light, and the second portion of the source light as the light scattered from the plurality of particles.

23. The system of claim 22, further comprising one or more mirrors positioned distally from the beam splitter and configured to direct the first portion of the source light to the light detector as reference light, and the second portion of the source light as the light scattered from the plurality of particles.

24. The system of claim 23, further comprising an optical attenuator positioned and configured to regulate intensity of the first portion of source light to be substantially the same as an intensity of the second portion of the source light.

25. The system of claim 21, wherein the light detector is positioned to be perpendicular or substantially perpendicular relative to the light emitted from the light source.

26. The system of claim 1, wherein the light source is located external to the container.

27. The system of claim 1, wherein the wall of the container is at least partially transparent to the source light.

28. A method to measure a size distribution among a plurality of particles in a medium, the method comprising:

producing motion of the medium and the plurality of particles therein;

emitting a source light from a light source toward the plurality of particles;

at a light detector, detecting light scattered from at least a portion the plurality of particles;

at a controller, determining intensities of light frequencies among the light scattered from the at least a portion of the plurality of particles; and

at the controller, determining a size distribution among the plurality or particles based at least partially on the determined intensities of corresponding light frequencies.

29. The method of claim 28, wherein producing the motion of the medium and the plurality of particles therein comprises producing an oscillating motion of the medium and of the plurality of particles therein.

30. The method of claim 28, wherein producing the motion of the medium and the plurality of particles therein comprises propagating a wave through the medium.

31. The method of claim 28, wherein producing the motion of the medium and the plurality of particles therein comprises moving a container that holds the medium and the plurality of particles.

32. The method of claim 28, wherein determining the size distribution among the plurality or particles based at least partially on the determined intensities of corresponding light comprises correlating light frequencies with corresponding particle sizes of the plurality of particles.

33. The method of claim 28, wherein emitting a source light from a light source toward the plurality of particles comprises emitting a monochromatic source light from the light source toward the plurality of particles.

34. The method of claim 28, further comprising, responsive to the exposing the plurality of particles to the source light from the light source, propagating waves in the medium containing the plurality of particles.

35. The method of claim 34, wherein propagating waves in the medium containing the plurality of particles comprises varying intensity of the waves.

36. The method of claim 28, further comprising exposing the light detector to a reference source light that did not scatter from the plurality of particles, wherein the source light is a monochromatic light, and the reference source light is a monochromatic light of the same frequency as the source light.

37. The method of claim 36, wherein exposing the plurality of particles to the source light from the light source and exposing the light detector to the reference source light comprises generating the monochromatic light of the reference source light and the monochromatic light of the source light from a single light source.

38. The method of claim 37, further comprising at least one of splitting, reflecting, or attenuating the monochromatic from the single light source to produce the reference source light.

39. The method of claim 36, wherein the monochromatic light of the reference source light and the source light have substantially the same intensity.