Patent Grant
9114606
This disclosure relates generally to techniques for performing system or sample analysis by evaluating light interacting with ink droplets. More particularly, the application relates to techniques for monitoring delivery of ink droplets in an inkjet printer, and to components, devices, systems, and methods pertaining to such techniques.
Ink jet printers operate by ejecting small droplets of liquid ink through a nozzle onto print media according to a predetermined pattern. In some implementations, the ink is ejected directly on a final print media, such as paper. In other implementations, the ink is ejected on an intermediate print media, e.g. a print drum, and is then transferred from the intermediate print media to the final print media.
On occasion, the nozzles of ink jet printers can become obstructed, blocked, or otherwise develop non-uniformities such that the droplets are ejected with an undesirable size, speed, trajectory, and/or are not ejected at all. Current droplet monitoring techniques use machine vision with strobed video or high speed camera. These techniques are expensive, time consuming, and can require extensive software development.
According to one embodiment, an apparatus for the ink jet printer that includes an ejector, a spatial filter, a detector, and an analyzer. The ejector is configured to release an ink droplet along a path and the spatial filter has a plurality of features. The detector is positioned to sense light emanating from the droplet along the path with the sensed light being modulated according to the features as the droplet moves along the path relative to the spatial filter. The detector is configured to generate a time-varying electrical signal in response to the sensed light. The analyzer determines one or more physical, spatial, or dynamic characteristics of the droplet based upon the time-varying signal.
In another embodiment, a system includes an ink jet print head, an optical component, one or more detectors, and an analyzer. The inkjet print head has a plurality of ejectors. Each ejector is configured to release one or more droplets along one or more paths. The optical component is configured to provide a measurement light. The one or more detectors are positioned to detect light emanating from each of the one or more droplets along the one or more paths in response to the measurement light. The detected light is modulated as the one or more droplets move along a detection region and the detector is configured to generate one or more time-varying signals in response to the detected light. The analyzer is configured to simultaneously distinguish and determine one or more dynamic, physical, and spatial characteristics of the one or more droplets and correlate each of the one or more droplets with one of the plurality of ejectors based upon the one or more time-varying signals.
Some embodiments involve a method of analyzing delivery of inkjet droplets from a print head that includes releasing a droplet from an ejector of the print head, sensing a modulated light from the droplet moving along a path relative to a spatial filter, generating a time-varying signal in response to the detected light, and analyzing the time-varying signal to determine one or more dynamic, physical, and spatial characteristics of the droplet based upon the time-varying signal.
Additional embodiments involve a method that includes sensing a modulated light from a ink droplet moving along a path relative to a spatial filter, generating a time-varying signal in response to the detected light, and analyzing the time-varying signal to determine one or more dynamic characteristics of the droplet including a separation of the droplet from a plurality of droplets, a combination of the droplet with one or more additional droplets, and a uniformity or non-uniformity of speed, size, trajectory, and shape of a group of sequentially released droplets including the droplet.
The above summary is not intended to describe each disclosed embodiment or every implementation of the present disclosure. The figures and the detailed description below more particularly exemplify illustrative embodiments.
Throughout the specification reference is made to the appended drawings wherein:
The figures are not necessarily to scale. Like numbers used in the figures refer to like components. However, it will be understood that the use of a number to refer to a component in a given figure is not intended to limit the component in another figure labeled with the same number.
Non-uniformities in the passages and nozzles of inkjet print heads can cause misplaced, intermittent, missing or weak ink jetting resulting in undesirable visual flaws in the final printed pattern. The disclosed techniques are applicable to desk jet as well as industrial print applications. In yet other implementations, the ink can be deposited onto previously deposited material for fabrication of a three dimensional object.
Although approaches are discussed with reference to ink droplets for inkjet printing, these approaches are also relevant to any application where the physical, spatial, dynamic and/or other characteristics of droplets are measured. This disclosure describes a monitoring and analysis device and related techniques, methods, systems, and apparatuses that can be used to monitor and analyze the characteristics of ink droplets ejected from an inkjet print head using light emanating from the ink droplets. More particularly, the application describes analysis techniques and an analyzer that can be used to measure physical, spatial and dynamic characteristics of the ink droplets such as droplet speed, shape, size, location, trajectory, uniformity of behavior between a group of droplets, splitting/combining of droplets, and composition based upon patterned light emanating from the ink droplets. Light emanating from the droplets can originate from a multitude of physical processes including: Fluorescence, scattering, up-conversion, second harmonic generation, multi-photon excited fluorescence, Raman scattering, phosphorescence, absorption etc.
The approaches described can aid in the monitoring and analysis of ink droplet delivery, as well as provide a cost effective and less complex alternative to strobed video or high speed camera methods.
In some embodiments, a control circuitry and/or software can be used in a feedback loop to vary one or more of the characteristics of the droplet based upon the determined one or more characteristics of a prior droplet(s).
It will be understood that the techniques, apparatuses, systems, and methods described herein are applicable to detect various droplet characteristics present in a sample. As used herein the term “droplet” refers broadly to droplets used in industrial applications and is not limited to desktop inkjet droplets. The term droplet can refer to one or more test droplets, droplets used during in-line printing application, a group of droplets from one or more ejectors, and a plurality of droplets from multiple ejectors monitored as part of a large scale array, etc. Thus, as used herein droplet includes one or more test droplets launched, monitored, and analyzed prior to or intermittent with normal printing operations (e.g., during warm-up, at desired intervals, prior to a large print job, etc.) The test droplets have characteristics that simulate the characteristics of droplets delivered to the print medium during normal in-line printing operation.
In some embodiments, one or more sensors can obtain information about the droplet by receiving a signal(s) therefrom; for example, the signal in the form of light can emanate from the droplet, whether through emission (e.g. radiation, fluorescence, incandescence, chemoluminescence, bioluminescence, other forms of luminescence, etc.), scattering (e.g. reflection, deflection, diffraction, refraction, etc.), or transmission, and can be sensed by a sensor such as a photodetector. Droplets may be treated, e.g., stained or tagged with a suitable fluorescent probe or other agent, in such a way that they emit light or absorb light in a predictable fashion when illuminated with excitation light. In this regard, the light emitted by a given excited droplet may be fluorescent in nature, or it may constitute a form of scattered light such as in the case of Raman scattering. For simplicity, the light that emanates (by e.g., scattering, emission, or transmission) from a droplet is referred to herein as “emanating light” “light emanating” or simply as “light” in some circumstances. Similarly, the light that emanates from a light source can be referred to as “excitation light”, “incoming light”, or “measurement light” herein. It will be understood that the techniques, assemblies, apparatuses, systems, and methods described herein are applicable to detecting all forms of light emanating from a droplet.
The embodiments described herein utilize various techniques and spatial filters disclosed in one or more of the Applicants' co-filed applications, application Ser. No. 14/181,560, entitled “Spatial Modulation of Light to Determine Object Position”, application Ser. No. 14/181,524, entitled “Spatial Modulation of Light to Determine Dimensional Characteristics of Objects in an Injection direction”, application Ser. No. 14/181,571, entitled “Determination of Color Characteristics of Objects Using Spatially Modulated Light”, and application Ser. No. 14/181,530, entitled “Spatial Modulation of Light to Determine Object Length”, co-pending herewith. These co-pending applications are herein incorporated by reference in their entirety.
In some embodiments, the concentration and/or presence of an analyte in a droplet can be measured using varies techniques, for example, as disclosed in co-owned U.S. patent application Ser. No. 13/826,198, entitled “Compositions and Methods for Performing Assays” (Recht et al.), filed Mar. 14, 2013, U.S. patent application Ser. No. 13/627,739, entitled “Multiplexed Flow Assay Based On Absorption-encoded Micro Beads”, (Kiesel et al.), filed Sep. 26, 2012, and U.S. Pat. App. Publ. No. 2013/0037726 (Kiesel et al.), the disclosures of which are incorporated herein by reference in their entirety.
These and other disclosed techniques can be deployed in a variety of printer applications for analysis of system properties and/or detection of various characteristics of droplets. As previously discussed, using the techniques disclosed herein, it is possible to determine one or more physical, spatial and dynamic characteristics of the ink droplets such as droplet speed, shape, size, location, trajectory, uniformity of behavior between a group of droplets, splitting/combining of droplets, and composition based upon patterned light emanating from the ink droplets. In some instances, the droplet composition can be obtained using florescence and can be indicative of a degradation of the ink in some instances. The size/shape of each droplet can be measured in up to three dimensions, and a three dimensional position of the droplet during a path to a medium can be determined. Additionally, as the droplet travels in time and space, additional information can be obtained including trajectory information such as angles of travel in up to three dimensions and the droplet speed.
Embodiments described herein may involve the use of at least one spatial filter and/or optics that provide patterned excitation light and/or may involve the use of at least one spatial filter and/or optics that spatially modulate the light emanating from the droplets. As each droplet moves along an injection direction, the droplet emanates light that is spatially modulated or otherwise patterned and detected by a detector. The detector generates a time-varying signal in response to the sensed patterned light. In some implementations, a non-imaging or non-pixilated photodetector can be used to generate the time-varying signal based on the patterned light.
The time-varying signal includes information about the droplet's characteristics (e.g., spatial, physical, and/or dynamic). In some embodiments, the time-varying signal can be analyzed in the time domain to extract the desired information regarding the droplet. For example, the time-varying signal may be compared or correlated to a known template signal and/or the time-varying signal may be analyzed by examining various morphological and durational characteristics of the time-varying signal. In some embodiments, the time-varying signal may be transformed from the time domain to the frequency domain and the analysis may be carried out on the frequency domain signal.
Each ejector 240 includes an actuator 250 that controls the ejection of the ink drops through a passage 260 and through an ink jet nozzle 270 onto the print medium, e.g., the drum. In some implementations, the actuator 250 comprises piezoelectric transducers (PZTs) for ink droplet ejection, although other methods of ink droplet ejection are known. Activation of the PZT causes a pumping action that alternatively draws ink into an inlet (not shown) from the finger manifolds 220 and expels the ink through the nozzle 270.
The detection region 320 receives a sample of interest to be analyzed moving along the path 323 illustrated. The sample may move along the detection region 320 generally along the x-direction illustrated. However, as discussed subsequently, the sample may additionally or alternatively move along the detection region in the y-direction and/or z-direction illustrated. Excitation light emitted by the light source 312 interacts with the sample in an excitation region 323a. In this regard, the light source 312 may emit incoming (excitation) light 312a towards the detection region 320 in some embodiments such as the embodiment illustrated in
In some cases, the light source 312 may comprise a conventional laser, a laser diode (LD), light emitting diode (LED) source, or a resonant cavity LED (RC-LED) source, for example. If desired, the light source may incorporate one or more filters to narrow or otherwise tailor the spectrum of the resultant output light. Whichever type of light source is selected, the spectral makeup or composition of the incoming light emitted by the light source 312 is preferably tailored to excite, scatter, or otherwise cause emanation of light from at least some of the droplets that may be present in the sample, as discussed further below.
The sample is depicted as containing droplets 305 that emanate light 307 in all directions (only some directions are illustrated). The droplets 305 may have a variety of characteristics, some of which can be determined by the analyzer 350 based on the emanating light 307.
The detector 330 receives time-varying light and generates an electrical signal in response to the time-varying light. The time variation in the light detected by the detector 330 may be the result of interaction between the excitation light and an input spatial filter to create spatially patterned excitation light that illuminates the droplet 305. Alternatively, the time variation in the light detected by the detector 330 may be the result of interaction between light emanating from the droplets 305 and an output spatial filter. In yet other embodiments, the time variation in the light detected by the detector 330 may be the result of excitation light or emanating light that is patterned using optical components such as micro-optics.
In some embodiments, the detector 330 includes an optical filter arranged between the detector and the objects. An optical filter can be particularly useful when the emanating light is fluorescent light and the optical filter is configured to substantially block the wavelengths of the excitation light and to substantially pass the wavelengths of the light emanating from the objects.
The assembly 300 of
In some configurations, indicated by arrow 326a, the spatial filter can be disposed between the detection region 320 and the detector 330. In this position, the spatial filter is referred to as an output spatial filter. In other configurations, indicated by arrow 326b, the spatial filter can be disposed between the light source 312 and the detection region 320. In this position, the spatial filter is referred to as an input spatial filter. An input spatial filter may be adapted to transmit light emitted by the light source by varying amounts along the excitation region 323a. In this configuration, the input spatial filter creates patterned excitation light in the excitation region 323a. According to various implementations, an input spatial filter may comprise a physical spatial filter including a sequence or pattern of first regions that have a first optical characteristic, e.g., are more light transmissive, and second regions that have a second optical characteristic, different from the first characteristic, e.g., are less light transmissive. In some implementations, the first regions may be substantially clear and the second regions may be substantially opaque at the wavelengths of interest. Alternatively or in addition to a spatial filter, one or more optical components such as micro-optics or a patterned light source configured to create the excitation pattern can be utilized. The excitation pattern can be imaged and/or directed onto the excitation region 323a using additional optical components for the imaging (e.g., lenses) and/or direction, (e.g., fiber optics or waveguides).
In some embodiments, an output spatial filter may be utilized and disposed between the detection region 320 and the detector 330. In some embodiments, the excitation region 323a and the detection region 320 overlap. In other embodiments, there may be partial overlap between the excitation region and detection region or the excitation and detection regions may be non-overlapping or multiple detection regions and/or excitation regions may be used with various overlapping and/or non-overlapping arrangements. In some embodiments, the output spatial filter may be a physical spatial filter comprising a sequence or pattern of first regions that are more light transmissive and second regions that are less light transmissive. In some embodiments, color spatial filters may be used such that a first region of the color spatial filter is more transmissive to a first wavelength band and less transmissive to a second wavelength band and a second region of the color spatial filter is less transmissive to the first wavelength band and is more transmissive to the second wavelength band. As the emanating light from the droplet travels along the detection region 320 relative to the output spatial filter 326, the more transmissive and less transmissive regions of the spatial filter 326 alternatively transmit and block the light emanating from the droplet, creating time modulated light that falls on the detector 330. In response, the detector 330 generates a time varying electrical output signal 334.
According to some embodiments of an assembly 300 that include an input spatial filter, as the droplet 305 travels in the injection direction 323c in the excitation region 323a, light emanating from the light source 312 is alternately substantially transmitted to the droplet 305 and substantially blocked or partially blocked from reaching the droplet 305 as the droplet 305 travels along the path 323. The alternate transmission and non-transmission (or reduced transmission) of the excitation light 312a along the path 323 within the detection region 320 produces time-varying emanating light 307 emanating from the droplet 305. The time-varying emanating light 307 emanating from the droplet 305 falls on the detector 330 and, in response, the detector 330 generates a time-varying electrical output signal 334.
In some embodiments, as illustrated in
For conversion, the signal processor 340 may use known techniques such as discrete Fourier transform including, for example, a Fast Fourier Transform “FFT” algorithm. Thus, the frequency domain output signal 336 represents the frequency component magnitude of the time-varying detector output signal 334, where the frequency component magnitude is the amount of a given frequency component that is present in the time-varying detector output signal 334 or function. The Fourier signal power is a relevant parameter or measure because it corresponds to the function or value one would obtain by calculating in a straightforward manner the Fourier transform (e.g. using a Fast Fourier Transform “FFT” algorithm) of the time-varying signal 334. However, other methods or techniques of representing the frequency component magnitude, or other measures of the frequency component magnitude, may also be used. Examples may include e.g. the square root of the Fourier signal power, or the signal strength (e.g. as measured in voltage or current) obtained from a filter that receives as input the time-varying detector output signal 334.
In
In some embodiments, a control circuitry 352 can be configured to vary one or more of the characteristics of the droplet 305 based upon the determined characteristics that result from the analyzer 350. Thus, the control circuitry 352 is configured to vary the one or more physical, spatial, or dynamic characteristics based upon the determined characteristics in some instances. For example, the control circuitry 352 can adjust a waveform of the piezoelectric transducer that drives the ejector (
As illustrated in
As discussed previously, the spatial filter 426 may comprise, for example, a mask. As will be discussed in greater detail subsequently, the spatial filter 426 may have a plurality of spatial filter features 470. The spatial filter features 470 include first features 470a having a first optical characteristic, e.g., more light transmissive regions, and second features 470b having a second optical characteristic, e.g., less light transmissive regions. For simplicity of explanation, many examples provided herein refer to spatial filter features comprising more light transmissive regions and spatial filter features or regions comprising less light transmissive regions. However, it will be appreciated that the optical characteristics of the first and second types of spatial filter features may differ optically in any way, e.g., the first features may comprise regions having a first optical wavelength pass band and the second features may comprise regions having a second optical wavelength pass band different from the first optical wavelength pass band. The pattern or sequence of first features 470a and second features 470b define a transmission function that affects light interacting with the spatial filter. When used as an output spatial filter, the interaction causes a time modulated signal that is dependent on the transmission function defined by the spatial filter and on a three dimensional position of a light 407 emanating from the droplet 405 (i.e., as measured along the x-direction, y-direction, and z-direction of the Cartesian coordinate system). This transmission function may be substantially periodic, or it may instead be substantially non-periodic. The time varying light transmitted by the spatial filter is sensed by the detector 430, which is configured to output the time-varying electrical output signal discussed in
In the embodiment of
A plurality of droplets 505 are illustrated entering the detection region 520 traveling along a path 523. In the embodiment of
In
According to some embodiments, the physical characteristics of the objects can comprise one or more of a three dimensional shape, a three dimensional size, a length of the object in the longitudinal direction relative to the spatial filter, a width of the droplet in a lateral direction relative to the spatial filter, a thickness of the droplet in a depth direction relative to the spatial filter, and a composition. The spatial characteristics can comprise one or more of a location and trajectory of the droplet in two or three dimensions. The dynamic characteristics can comprise one or more of a speed of the droplet, a separation of the droplet into a plurality of droplets, a combination of the droplet with one or more additional droplets, and a uniformity or non-uniformity of speed, size, trajectory, and shape of a group of incrementally released droplets including the droplet.
In the embodiment of
As discussed, in some instances each spatial filter 626a, 626b, 626c, and 626d can include less or more than four regions. Additionally, different groups of features may be disposed within the same region (interdisposed). The longitudinal arrangement of the different groups of features may be changed from embodiment to embodiment. For example, the first group 601a, 601b, 601c, and 601d of features used to determine the speed may be disposed in other regions. Not all regions may be used in some embodiments.
As illustrated in
Spatial filter 726 can also be used to determine one or more dynamic characteristics of droplets 705a, 705b, and 705c. In particular, if droplets 705a, 705b, and 705c are released from an ejector as a sequential group the spatial filter 726 can be useful to determine dynamic characteristics such as a uniformity or non-uniformity of speed, size, trajectory, and shape of the group as these characteristics can impact printing accuracy and clarity. As shown in
It should be appreciated that a droplet undergoing a combination dynamic characteristic, (i.e. a phenomenon where a first droplet combines with a second droplet and perhaps additional droplets) can be identified in a manner somewhat similar to that described in
The arrangement makes use of an optical component 980 such as a lens to focus light on a detector 930. In some embodiments, the detector 930 comprises a wide-area detector. The large area detector can determine which of the plurality of ejectors 940a, 940b, 940c, and 940d a droplet was released from and in some instances can simultaneously distinguish between trajectories of multiple droplets. For example, during printer warm-up each ejector 940a, 940b, 940c, and 940d may release a particle at a different time, such as sequentially, allowing for analysis of the droplets released with the large area detector. Additionally or alternatively, the features of each spatial filter 926a, 926b, 926c, and 926d can be sufficiently different such that analysis of the resulting time-varying signal for signature patterns would allow for determination of which of the ejectors 940a, 940b, 940c, and 940d the droplet was released from. In some instances, if two or more droplets are released from ejectors 940a, 940b, 940c, and 940d simultaneously complex data analysis can be used to separate the signals components and identify which of the ejectors 940a, 940b, 940c, and 940d the droplets were released from. Although it can be difficult to extract detailed information on the signal shape with two or more droplets released simultaneously, with a simple spatial filter 926a, 926b, 926c, and 926d arrangement such as shown in
Detector 930 can be used to capture modulated light from multiple droplets passing through the multiple spatial filters 926a, 926b, 926c, and 926d. The detector 930 can output a time-varying signal to the analyzer 950 to determine characteristics of the droplets including but not limited to the speed. Thus, the spatial filters 926a, 926b, 926c, and 926d, analyzer 950, and detector 930 allow for distinction between multiple simultaneously imaged droplets. The analyzer 950 can be configured to perform parallel analysis on the time-varying signal in order to provide diagnostics on an inkjet print head to identify which of the ejectors 940a, 940b, 940c, and 940d may be in need of repair or adjustment.
A plurality of detectors 1030a, 1030b, 1030c, 1030d, 1030e, 1030f, 1030g, and 1030h are illustrated in the embodiment of
Each detector 1030a, 1030b, 1030c, 1030d, 1030e, 1030f, 1030g, and 1030h generates a time-varying signal that is passed to the analyzer 1050 which can determine which of the plurality of ejectors 1040a, 1040b, 1040c, 1040d, 1040e, 1040f, 1040g, and 1040h the droplet was released from and can simultaneously distinguish between trajectories, speed, etc. of multiple droplets.
As shown in
The spatial filter 1126 includes several less transmissive feature patterns 1170b, 1171b, and 1172b. In particular, the first less transmissive feature pattern 1170b is centered between the second less transmissive feature pattern 1171b and the third less transmissive feature pattern 1172b. In the exemplary embodiment, the first less transmissive feature pattern 1170b includes less transmissive features that have a curved shape with a known size, shape (including angles) and relative spacing. This known geometry allows for even slight deviations in the path of a droplet to be detected using analysis of the time-varying signal. In some instances, the first less transmissive feature pattern 1170b is used as the primary feature pattern for identifying a desired path of droplets to the print medium. Thus, droplet 1105a and path 1123a are shown as illustrating the desired path of a droplet.
The second less transmissive feature pattern 1171b is disposed laterally adjacent the first less transmissive feature pattern 1170b and has a known size, shape (including angles) and relative spacing both in relation to its own features and in relation to the first less transmissive feature pattern 1170b. A portion of each less transmissive feature in the second less transmissive feature pattern 1171b additionally extends longitudinally adjacent the less transmissive features of the first less transmissive feature pattern 1170b. Thus, to some extent the second less transmissive feature pattern 1171b is interleaved with the first less transmissive feature pattern 1170b. The third less transmissive feature pattern 1172b is mirrored to the second less transmissive feature pattern 1171b in the exemplary embodiment. Thus, the third less transmissive feature pattern 1172b is to some extent interleaved with the first less transmissive feature pattern 1170b in the manner described previously. The extent of such interleaving is a matter of design preference. A greater degree of interleaving will better capture smaller angles of deviation from the desired path (e.g., path 1123a). One such deviation from the desired path is illustrated by path 1123b. Thus, in some instances the second less transmissive feature pattern 1171b and/or the third less transmissive feature pattern 1172b can be used as the primary feature pattern(s) for identifying a deviation from the desired path.
In particular, the second time-varying signal 1180b can be used to determine trajectory information such as angles relative to the desired path. It should be noted from comparison of first time-varying signal 1180a of
The spatial filter 1226 can include several less transmissive feature patterns, however, only less transmissive feature patterns 1270b and 1271b are illustrated. In the exemplary embodiment, the first less transmissive feature pattern 1270b includes less transmissive features that have a curved shape with a known size, shape (including angles) and relative spacing.
The second less transmissive feature pattern 1271b is disposed laterally adjacent the first less transmissive feature pattern 1270b and has a known size, shape (including angles) and relative spacing both in relation to its own features and in relation to the first less transmissive feature pattern 1270b. In the embodiment illustrated, a first more transmissive feature pattern 1270a has a dimension (e.g., area) that is roughly twice that of a second more transmissive feature pattern 1271a. Additionally shown in
In some instances, the method can additionally include a plurality of ejectors and the spatial filter has a plurality of features with a varied arrangement for each of the plurality of ejectors. Additionally, the method can perform parallel analysis on the time-varying signal in order to provide diagnostics on the print head in some embodiments. In additional embodiments, the method can additionally provide a fluorescence light to the droplet to excite the fluorescence within the droplet to generate light from the droplet. In further methods, a waveform of a piezoelectric transducer that drives the ejector can be adjusted.
In yet another embodiment, a method is disclosed that senses a modulated light from an ink droplet moving along a path relative to a spatial filter. The method generates a time-varying signal in response to the detected light. The time-varying signal is analyzed to determine one or more dynamic characteristics of the droplet including a separation of the droplet into a plurality of droplets, a combination of the droplet with one or more additional droplets, and a uniformity or non-uniformity of speed, size, trajectory, and shape of a group of sequentially released droplets including the droplet.
Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as representative forms of implementing the claims.
| Number | Name | Date | Kind |
|---|---|---|---|
| 6213579 | Cornell et al. | Apr 2001 | B1 |
| 7104634 | Weksler et al. | Sep 2006 | B2 |
| 7358476 | Kiesel et al. | Apr 2008 | B2 |
| 7386199 | Schmidt et al. | Jun 2008 | B2 |
| 7420677 | Schmidt et al. | Sep 2008 | B2 |
| 7547904 | Schmidt et al. | Jun 2009 | B2 |
| 7688427 | Cox et al. | Mar 2010 | B2 |
| 7701580 | Bassler et al. | Apr 2010 | B2 |
| 7894068 | Bassler et al. | Feb 2011 | B2 |
| 8203711 | Shinoda | Jun 2012 | B2 |
| 8373860 | Kiesel et al. | Feb 2013 | B2 |
| 8388569 | Uhland et al. | Mar 2013 | B2 |
| 8629981 | Martini et al. | Jan 2014 | B2 |
| 20080181827 | Bassler et al. | Jul 2008 | A1 |
| 20080183418 | Bassler et al. | Jul 2008 | A1 |
| 20120194590 | Suzuki | Aug 2012 | A1 |
| 20120236291 | Pittaro et al. | Sep 2012 | A1 |
| 20120271221 | Uhland et al. | Oct 2012 | A1 |
| 20130016335 | Lo et al. | Jan 2013 | A1 |
| 20130037726 | Kiesel et al. | Feb 2013 | A1 |
| Number | Date | Country |
|---|---|---|
| WO0194938 | Dec 2001 | WO |
| WO2005017969 | Feb 2005 | WO |
| Entry |
|---|
| U.S. Appl. No. 14/155,094, Martini et al., filed Jan. 14, 2014. |
| U.S. Appl. No. 14/181,524, Martini et al., filed Feb. 14, 2014. |
| U.S. Appl. No. 14/181,530, Martini et al., filed Feb. 14, 2014. |
| U.S. Appl. No. 14/181,560, Kletter et al., filed Feb. 14, 2014. |
| U.S. Appl. No. 14/181,571, Martini et al., filed Feb. 14, 2014. |
| Kiesel et al., “Spatially Modulated Fluorescence Emission from Moving Particles”, Appl. Phys. Lett. 94, 2009, pp. 041107-1-041107-3. |
| Kiesel et al., “Spatially Modulated Emission Advances Point-of-Care Diagnostics”, Laser Focus World, Nov. 2010, pp. 47-50. |
| Petersson et al., “Free Flow Acoustophoresis: Micorfluidic-Based Mode of Particle and Cell Separation”, Anal. Chem, 79 (14), 2007, pp. 5117-5123. |
| Yamada et al., “Pinched flow fractionation: continuous size separation of particles utilizing a laminar flow profile in a pinched microchannel”, Anal. Chem. 76 (18), Sep. 2004, pp. 5465-5471. (abstract only). |
| Yamada et al., “Microfluidic Particle Sorter Employing Flow Splitting and Recombining”, Anal. Chem. 78, 2006, pp. 1357-1362. |
| Ji et al., “Silicon-based microfilters for whole blood cell separation”, Biomed Microdevices 10(2), 2008, pp. 251-257. (abstract only). |
| Schrum et al., “Microchip Flow Cytometry Using Electrokinetic Focusing”, Anal. Chem. 71 (19), Oct. 1999, pp. 4173-4177. (abstract only). |
| Huh et al., “Microfluidics for flow cytometric analysis of cells and particles” Physiol. Meas. 26 (3), Jun 2005, pp. R73-98. (abstract only). |
| Fu et al., “Electrokinetically driven cytometers with integrated fiber optics for on-line cell/participle detection”, Analytica Chimica ACTA, Vo. 507 (1), Apr. 2004, pp. 163-169. (abstract only). |
| Lee, Gwo-Bin et al., “Micromachine-based multi-channel flow cytometers for cell/particle counting and sorting”, J. Micromech, Microeng. 15 (2005) 447-454. (abstract only). |
| Lin et al., “Vertical focusing device utilizing dietectrophoretic force and its application on mlcroflow cytometer”, Journal of Microelectrormechanical Systems, vol. 13, No. 6, Dec. 2004, 10 pages. |
| Zhu et al., “Dielectrophoretic focusing of particles in a microchannel constriction using DC-biased AC flectric fields”, Electrophoresis, vol. 30 (15), Jul. 2009. (abstract only). |
| Chu et al., “A three-dimensional (3D) particle focusing channel using the positive dielectrophoresis (pDEP) guided by a dielectric structure between two planar electrodes”, Lab on a Chip, Issue 5m 2009, pp. 688-691. (abstract only). |
| Chang et al., Three-dimensional hydrodynamic focusing in two-layer polydimethylsiloxane (PDMS) microchannels, J. Michromech. Microeng 17, 2007, pp. 1479-1486. |
| Sheng et al., “Digital holographic microscope for measuring three-dimensional particle distributions and motions”, Applied Optics, Vo. 45 (16), Jun. 2006, pp. 3893-3901. |
| Lindken et al., “Stereoscopic micro particle image velocimetry” Experiments in Fluids, 41, 2006, pp. 161-171. |
| Pereira et al., “Microscale 3D flow mapping with μDDPIV”, Experiments in Fluids, vol. 42 (4), Apr. 2007, pp. 589-599. (abstract only). |
| Cheong et al., “Flow Visualization and Flow Cytometry with Holographic Video Microscopy”, Optics Express 17, 2009, pp. 13071-13079. |
| Lima et al., “Confocal micro-PIV measurements of three dimensional profiles of cell suspension flow in a square microchannel”, Measurement Science and Technology, vol. 17, 2006, pp. 797-808. |
| Pugia et al., “Microfluidic Tool Box as Technology Platform for Hand-Held Diagnostics”, Clinical Chemistry, vol. 51 (10), 2005, pp. 1923-1932. |
| File History for U.S. Appl. No. 13/206,436 as retrieved from the U.S. Patent and Trademark Office Pair System on Feb. 14, 2014, 119 pages. |
| File History for U.S. Appl. No. 12/024,490 as retrieved from the U.S. Patent and Trademark Office Pair System on Feb. 14, 2014, 376 pages. |
| File History for U.S. Appl. No. 12/762,702 as retrieved from the U.S. Patent and Trademark Office Pair System on Feb. 14, 2014, 377 pages. |
| File History for U.S. Appl. No. 13/113,021 as retrieved from the U.S. Patent and Trademark Office Pair System on Feb. 14, 2014, 704 pages. |
