Patent Publication Number: US-10778911-B2

Title: Optical transformation device for imaging

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is related to U.S. non-provisional patent applications entitled, “System and Device for Optical Transformation” and “Device for Optical Imaging,” filed the same day. 
     BACKGROUND INFORMATION 
     Imaging devices are used in contexts such as healthcare, navigation, and security, among others. Imaging systems often measure radio waves or light waves to facilitate imaging. Imaging that measures light scattered by an object is especially challenging and advances to the devices, systems, and methods to improve optical imaging are sought to increase speed, increase resolution, reduce size and/or reduce cost. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Non-limiting and non-exhaustive embodiments of the invention are described with reference to the following figures, wherein like reference numerals refer to like parts throughout the various views unless otherwise specified. 
         FIGS. 1A-1C  illustrate an example imaging system that includes a display pixel array, an image pixel array, and a beam splitter, in accordance with an embodiment of the disclosure. 
         FIGS. 2A-2C  illustrate an example imaging system that includes an optical structure disposed between a display pixel array and an image pixel array, in accordance with an embodiment of the disclosure. 
         FIG. 3  illustrate an optic that may be included in the optical structure of  FIGS. 2A-2C , in accordance with an embodiment of the disclosure. 
         FIG. 4  illustrates an example placement of components of an imaging system in relationship to a human head, in accordance with an embodiment of the disclosure. 
         FIG. 5  illustrates example optical transform logic with dedicated parallel processing pipelines coupled between a tiled image pixel array and a tiled display pixel array, in accordance with an embodiment of the disclosure. 
         FIG. 6  illustrates example optical transform logic coupled between an image pixel array and a display pixel array, in accordance with an embodiment of the disclosure. 
         FIG. 7  illustrates a flow chart illustrating an example process of executing an optical transformation, in accordance with an embodiment of the disclosure. 
         FIGS. 8A-8B  illustrate an example imaging system that includes an image pixel array and extraction logic, in accordance with an embodiment of the disclosure. 
         FIG. 9  illustrates an image pixel array coupled to example extraction logic, in accordance with an embodiment of the disclosure. 
         FIG. 10  illustrates a flow chart illustrating an example process of optical imaging, in accordance with an embodiment of the disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments of a system, device, and method for optical imaging of a diffuse medium are described herein. In the following description, numerous specific details are set forth to provide a thorough understanding of the embodiments. One skilled in the relevant art will recognize, however, that the techniques described herein can be practiced without one or more of the specific details, or with other methods, components, materials, etc. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring certain aspects. 
     This disclosure will generally describe imaging a diffuse medium in the context of human tissue in the medical context, however, the content of this disclosure may be applied to medical imaging, navigation, security, scientific research, or other contexts that image diffuse mediums or objects. 
     Human tissue is translucent to infrared light, although different parts of the human body (e.g. skin, blood, bone) exhibit different absorption coefficients. Researchers have attempted to use the properties of infrared light for medical imaging purposes, but size and cost constraints have been prohibitive for wide-scale adoption. Illuminating tissue and other diffuse mediums with near-infrared light for imaging purposes is sometimes referred to as Diffuse Optical Tomography. In one Diffuse Optical Tomography technique, time-of-flight (TOF) imaging can theoretically be employed by measuring the time it takes for “ballistic” photons (those photons that are not scattered) to pass through tissue. Since the ballistic photons reach the sensor the fastest, they are the least impeded (have the shortest optical path) and thus some conclusion can be drawn to create an image of the tissue that is illuminated by infrared light. However, TOF imaging generally requires specialty hardware (e.g. picosecond pulsed lasers and single photon detectors) to facilitate ultrafast shutters on sensors that are able to image at the speed of light and the systems are overall very expensive and bulky. TOF imaging also requires an input of approximately 10-100 fold (or more) light intensity into the body than is used at the detector; thus efficacy and power limitations as well as safety limits on input intensity limit TOF imaging resolution and utility. 
     In contrast to TOF imaging, embodiments of this disclosure utilize a holographic imaging signal to direct infrared light to a voxel of a diffuse medium (e.g. a brain or tissue). A device or system of the disclosure may illuminate a diffuse medium with an infrared light while an ultrasound emitter is focused on a particular voxel. The infrared light encountering the particular voxel may be wavelength-shifted by the ultrasonic signal. The wavelength-shifted infrared imaging signal can be measured by a light detector (e.g. image pixel array). An optical transformation may be performed to generate a holographic pattern to be driven onto a display pixel array. When the display pixel array is illuminated by a light source having the same wavelength as the wavelength shifted infrared imaging signal, (while the holographic pattern is driven onto the display pixel array), a reconstructed version of the received wavelength-shifted infrared imaging signal may be directed back to the voxel to focus on the voxel so that an exit signal generated by the voxel can be measured by a sensor. The exit signal is the infrared light of the holographic beam that is reflected from and/or transmitted through the voxel. By capturing images of the exit signal changes (e.g. oxygen depletion in red blood cells, scattering changes induced by potential differences in an activated neuron, fluorescent contrast agents and other optical changes) at a voxel or group of voxels in the diffuse medium, changes to that voxel or group of voxels can be recorded over time. 
     In an embodiment of the disclosure, a device or system illuminates a diffuse medium with an infrared light while an ultrasound emitter is focused on a particular voxel. The infrared light encountering the particular voxel may be wavelength-shifted by the ultrasonic signal. The wavelength-shifted infrared imaging signal can be measured by a light detector (e.g. image pixel array). Extraction logic may isolate the wavelength-shifted infrared imaging signal and extract intensity data and then populate a voxel value of a composite image with the intensity data. The composite image may include a three-dimensional image of the diffuse medium. 
     These embodiments and others will be described in more detail with references to  FIGS. 1-10 . 
     Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. 
     Throughout this specification, several terms of art are used. These terms are to take on their ordinary meaning in the art from which they come, unless specifically defined herein or the context of their use would clearly suggest otherwise. 
       FIGS. 1A-1C  illustrate an example imaging system that includes a display pixel array, an image pixel array, and a beam splitter, in accordance with an embodiment of the disclosure. In  FIG. 1A , imaging system  100  includes processing logic  101 , a spatial light modulator (SLM)  110 , and image module  160 . The illustrated SLM  110  includes infrared (IR) light director  106  and display pixel array  113  and imaging module  160  includes image pixel array  170  and filter(s)  173 . In  FIG. 1A , imaging system  100  also includes a directional ultrasonic emitter  115  coupled to be driven by processing logic  101 . In  FIG. 1A , SLM  110  includes an infrared emitter  105 , an infrared light director  106 , and a display pixel array  113 . Display pixel array  113  may be an LCD (liquid crystal display), for example. The LCD display may be an active-matrix (using thin-film-transistors) or a passive matrix LCD. In one embodiment, the LCD display has pixels that are less than 7 microns. In other embodiments, SLM  110  may include a reflective architecture such as a liquid-crystal-on silicon (LCOS) display being illuminated by infrared light, for example. Other known transmissive and reflective display technologies may also be utilized as SLM  110 . System  100  may include a plurality of discrete devices that incorporate components of system  100 , in some embodiments. 
     Processing logic  101  may include a processor, microprocessor, cluster of processing cores, FPGA (field programmable gate array), and/or other suitable combination of logic hardware. In some embodiments, memories (not illustrated) are integrated into the processing logic to store instructions to execute operations and/or store data. An external memory or memories (not illustrated) may also be coupled to processing logic  101  to store instructions to execute operations and/or store data. A “memory” or “memories” described in this disclosure may include volatile or non-volatile memory architectures. 
     System  100  includes an infrared illuminator  151 . Processing logic  101  is coupled to selectively activate IR illuminator  151  via output X2, in the illustrated embodiment. Infrared illuminator  151  may include an infrared laser generating a general illumination emission  152 . Of course, an infrared laser may generate monochromatic coherent infrared light. Monochromatic light may be defined as light within a 4 nm frequency band, for example. The infrared light that IR illuminator  151  emits may be centered around a frequency in the 680-1000 nm range. In one embodiment, the infrared light that IR illuminator  151  emits may be centered around a frequency in the 1600-1700 nm range. In one example, IR illuminator  151  generates monochromatic light centered around 680 nm. In one example, IR illuminator  151  generates monochromatic light centered around 850 nm. The infrared illuminator  151  is disposed to direct the general illumination emission  152  into the diffuse medium  130 . In the context of tissue, general illumination emission  152  will be significantly scattered within tissue within as little as 1 cm of depth into the tissue when tissue is the diffuse medium  130 . At least a portion of the general illumination emission  152  will encounter voxel  133 , as illustrated in  FIG. 1A . 
     System  100  also includes an ultrasonic emitter  115 . Ultrasonic emitter  115  is configured to focus an ultrasonic signal  117  to a point in three-dimensional space. In the medical context, the ultrasonic emitter  115  is configured to focus an ultrasonic signal  117  to a voxel within the human body. The voxel may be within the brain, abdomen, or uterus, for example. Processing logic  101  is coupled to drive directional ultrasonic emitter  115  to focus ultrasonic signal  117  to different locations in three-dimensional space via output X1, in the illustrated embodiment. The directional ultrasonic emitter  115  can be driven to focus an ultrasonic signal to voxel  133  in three-dimensional diffuse medium  130 , for example. Focusing an ultrasonic signal  117  to a given voxel of tissue (e.g. voxel  133 ) influences the portion of general illumination emission  152  that encounters the voxel by wavelength-shifting that portion of the general illumination emission  152 . 
     In  FIG. 1B , the wavelength-shifted portion of the general illumination emission  152  is illustrated as shifted infrared imaging signal  143 . Being influenced by ultrasonic signal  117 , shifted signal  143  has a different wavelength (hereinafter referred to as lambda-two) than general illumination emission  152  (referred to as lambda-one). In some embodiments, the delta between lambda-one and lambda-two may be less than 1 nanometer. 
     System  100  receives (at least a portion of) shifted infrared imaging signal  143 . An input optic  147  may optionally be included in system  100 . Input optic  147  may receive shifted signal  143  and focus the shifted signal  143  to be incident on image pixel array  170 . In one embodiment, input optic  147  is configured to filter out an angled portion of the shifted signal  143 . In one embodiment, the angled portion of the shifted signal  143  has a plus-or-minus angle of incidence upon the input optic  147  that is higher than an angle threshold. In one embodiment, the sine of the angle threshold is approximately equivalent to a wavelength of the shifted signal  143  (lambda-two) divided by a distance between two pixels of the image pixel array  170 . In one embodiment, the angle threshold is between five and seven degrees. 
     Still referring to  FIG. 1B , reference wavefront generator  155  generates an infrared reference wavefront  157  having the lambda-two wavelength so that infrared reference wavefront  157  interferes with the incoming shifted signal  143 . Reference wavefront generator  155  may include one or more laser diodes and corresponding optics to generate a substantially uniform wavefront. Processing logic  101  is coupled to selectively activate reference wavefront generator  155  via output X3, in the illustrated embodiment. 
     A first portion of the infrared reference wavefront  157  is redirected to the image pixel array  170  by beam splitter  153  while a second remaining portion of wavefront  157  passes through beam splitter  153 . Shifted signal  143  encounters beam splitter  153  and a first portion of the shifted signal  143  passes through beam splitter  153  while the remaining second portion of the shifted signal  143  is reflected by beam splitter  153 . The first portion of the shifted signal  143  that passes through beam splitter  153  interferes with the first portion of wavefront  157  that is redirected to image pixel array  170  and image pixel array  170  captures an infrared image of the interference between shifted signal  143  and infrared reference wavefront  157 . 
     In one embodiment, reference wavefront generator  155  is disposed to deliver the infrared reference wavefront  157  to the image pixel array  170  at an angle to a pixel plane of the image pixel array  170 . Image pixel array  170  may include image pixels disposed in a two-dimensional rows and columns that define the pixel plane of the image pixel array  170 . In one embodiment, the angle is between five and seven degrees so that the infrared reference wavefront  157  encounters the image pixels of image pixel array  170  at a non-orthogonal angle. Angling the infrared reference wavefront  157  may increase the interference between shifted signal  143  and wavefront  157 , which may increase the interference signal for capturing by image pixel array  170 . Processing logic  101  is coupled to initiate the image capture by image pixel array  170  via output X5, in the illustrated embodiment. 
     A linear polarizer is included in system  100  to polarize shifted signal  143  to have the same polarization orientation as infrared reference wavefront  157 . The light source of reference wavefront generator  155  may generate linear polarized light which imparts a polarization orientation to infrared reference wavefront  157 . The linear polarizer may be included in optic  147 , filter  173 , or in a linear polarizer disposed between optic  147  and filter  173 , in  FIG. 1 . 
     In the illustrated embodiment, an infrared filter  173  is disposed between beam splitter  153  and image pixel array  170 . Infrared filter  173  passes the wavelength of infrared light emitted by reference wavefront generator  155  (lamda-two) and rejects other light wavelengths that image pixel array  170  is sensitive to. Infrared filter  173  may be configured to reject ambient light that is other than the lambda-two wavelength. 
     Image pixel array  170  may be implemented with an a-Si (amorphous Silicon) thin film transistors, in some embodiments or a CMOS (Complimentary Metal-Oxide-Semiconductor) image sensor, in some embodiments. Image pixel array  170  can be a commercially available image sensor. In one embodiment, image pixel array  170  has image pixels having a pixel pitch of 3.45 microns. In one embodiment, image pixel array  170  has image pixels having a pixel pitch of 1.67 microns. The pixel resolution of image pixel array  170  may vary depending on the application. In one embodiment, the image pixel array  170  is 1920 pixels by 1080 pixels. In one embodiment, the image pixel array is 40 Megapixels or more. Image pixel array  170  can capture an infrared image of an interference between shifted signal  143  and IR reference wavefront  157  by measuring the image charge generated in each pixel during a given integration period that is determined by an electronic shutter. The electronic shutter may be a global shutter (where each pixel measures the incident light during a same time period) rather than a rolling shutter. The electronic shutter can be actuated by processing logic  101  via input/output X5. Input/output X5 may include digital input/output lines as well as a data bus. Image pixel array  170  is communicatively coupled to optical transform logic  150  to send the captured infrared image(s) to optical transform logic  150 . for further processing. Image pixel array  170  may include a local (on-board) digital signal processor (DSP), in some embodiments, and optical transform logic  150  may receive the captured infrared images from the DSP. 
     Optical transform logic  150  is coupled to image pixel array  170  via communication channel X7, in the illustrated embodiment. Optical transform logic is also communicatively coupled to processing logic  101  via communication channel X6. Optical transform logic  150  is coupled to receive the captured infrared image from the image pixel array and provide a holographic pattern to be driven onto the display pixel array  113 . The optical transform logic  150  is configured to extract phase data of the interference captured by the infrared image and the holographic pattern is generated from the phase data. A more detailed description of example optical transform logic is presented below in association with  FIGS. 5-7 . 
     Referring now to  FIG. 1C , display pixel array  113  is configured to generate an infrared holographic imaging signal  144  (reconstruction of signal  143 ) according to a holographic pattern driven onto the array  113 . Optical transform logic  150  is coupled to provide the array  113  the holographic pattern to array  113  via communication channel X8. 
     In  FIG. 1C , display pixel array  113  is illustrated as a transmissive LCD that is illuminated by infrared wavefront  107 . In the illustrated embodiment, infrared (IR) emitter  105  is coupled to be driven by output X4 of processing logic  101 . When processing logic  101  turns on (activates) IR emitter  105 , infrared light propagates into IR light director  106 . IR light director  106  may be a light guide plate similar to those found in conventional edge lit LCDs. IR light director  106  may be a slim prism utilizing TIR (total internal reflection). IR light director  106  redirects the infrared light toward display pixel array  113 . IR light director  106  may include a sawtooth grating to redirect the infrared light toward array  113 . IR emitter  105  is an infrared laser diode that emits monochromatic infrared light, in one embodiment. 
     Steerable infrared beams can be generated by SLM  110  by driving different holographic patterns onto display pixel array  113 . Each different holographic pattern can steer (focus) the infrared light in a different direction. The directional nature of the infrared beam is influenced by the constructive and destructive interference of the infrared light emitted from the pixels of SLM  110 . As an example, a holographic pattern that includes different “slits” at different locations can generate different infrared beams. The “slits” can be generated by driving all the pixels in the display pixel array  113  to “black” (not transmissive) except for the pixels where the “slits” are located are driven to be “white” (transmissive) to let the infrared light propagate through. The pixel size of display pixel array  113  may be 1 micron, although in some embodiments pixels sized up to 10 times the wavelength of the infrared light can be used. In one example, if IR emitter  105  is an 850 nm laser diode, the pixel size of SLM  110  may be 850 nm. The pixel size influences the angular spread of a hologram since the angular spread is given by the Grating Equation:
 
sin(θ)= mλ/d   (Equation 1)
 
where θ is the angular spread of light, m is an integer number and the order of diffraction, and d is the distance of two pixels (a period). Hence, smaller pixel size generally yields more design freedom for generating holographic beams, although pixels sizes that are greater than the wavelength of light can also be used to generate holographic imaging signals. Display pixel array  113  may include square pixels (rather than the rectangular pixels in conventional RGB LCDs) so that the Grating Equation is applicable in both the row dimension and column dimension of the display pixel array  113 .
 
     In the illustrated embodiment, processing logic  101  selectively activates infrared emitter  105  and infrared light director  106  directs the infrared light to illuminate display pixel array  113  as infrared wavefront  107  while the holographic pattern is driven onto array  113 . Infrared wavefront  107  is the same wavelength as infrared reference wavefront  157 . Processing logic  101  may deactivate reference wavefront generator  155  while display pixel array  113  is being illuminated by infrared wavefront  107 . Processing logic  101  may be configured to drive the reference wavefront generator  155  to emit the infrared reference wavefront  157  and initiate the infrared image capture by the image pixel array  170  while the reference wavefront generator  155  and the infrared illuminator  151  are emitting the infrared reference wavefront  157  and the general illumination emission  152 , respectively. 
     Display pixel array  113  generates an infrared holographic imaging signal when the holographic pattern is illuminated by infrared wavefront  107  and the infrared holographic imaging signal is redirected by beam splitter  153  to exit system  100  as a reconstruction  144  (in reverse) of the shifted signal  143  that entered system  100 . Reconstructed signal  144  follows (in reverse) whatever scattered path that shifted signal  143  took from voxel  133  to beam splitter  153  so reconstructed signal  144  is essentially “focused” back onto voxel  133 . 
     Voxel  133  may absorb or scatter reconstructed signal  144  according to biological characteristics of voxel  133  and sensors may measure an exit signal  145  of the reconstructed signal  144  that encounters voxel  133 . System  100  may optionally include a sensor  190  coupled to processing logic  101  via an input/output X9 to initiate light measurement of exit signal  145  and pass the light measurement to processing logic  101 . Although exit signal  145  is illustrated as being directed to sensor  190 , the illustrated exit signal  145  is only a portion of the exit signal  145  that will be generated from signal  144  encountering voxel  133  and exit signal  145  will have many exit points from diffuse medium in addition to the illustrated portion of exit signal  145 . The sensors that measure this exit signal may simply measure the amplitude of the exit signal. Sensor  190  may be a photodiode or a CMOS image sensor, for example. In one embodiment, the image pixel array  170  is used to measure the amplitude and/or phase of exit signal  145 . The amplitude and/or phase of the exit signal  145  may be used to generate an image of diffuse medium  130 . A reconstructed signal  144  may be directed to voxel  133  multiple times (with multiple corresponding measurements of exit signal  145 ) so that biological changes in voxel  133  may be recorded over a time range. 
     System  100  may refocus directional ultrasonic emitter  115  to different voxels of diffuse medium  130  and repeat the processes disclosed herein to raster scan diffuse medium  130  in order to generate a three-dimensional image of diffuse medium  130 . Driving different holographic patterns onto display pixel array gives display pixel array  113  the ability to generate steerable holographic infrared beams that can focus the an infrared signal (e.g.  144 ) to different voxels in three-dimensional space to facilitate the raster scanning of diffuse medium  130 . 
     In one embodiment, processing logic  101  is configured to drive the reference wavefront generator  155  to emit the infrared reference wavefront  157  and initiate the infrared image capture by the image pixel array  170  while the reference wavefront generator  155  and the infrared illuminator  151  are emitting the infrared reference wavefront  157  and the general illumination emission  152 , respectively. 
       FIGS. 2A-2C  illustrate an example imaging system  200  that includes an optical structure disposed between a display pixel array and an image pixel array, in accordance with an embodiment of the disclosure. System  200  illustrated in  FIGS. 2A-2C  functions similarly to system  100  of  FIGS. 1A-1C  although there are differences associated with the different positioning of the SLM  210 , the imaging module  260 , and the addition of optical structure  280 . 
     Similarly to  FIG. 1A , in  FIG. 2A , processing logic  201  is coupled to drive directional ultrasonic emitter  115  to focus ultrasonic signal  117  to different locations in three-dimensional space, via output X1. Processing logic  201  is also coupled to selectively activate IR illuminator  151  via output X2, in the illustrated embodiment. System  200  may include a plurality of discrete devices that incorporate components of system  200 , in some embodiments. 
     Imaging module  260  includes image pixel array  270  and filter(s)  273 . In  FIG. 2A , imaging system  200  also includes a directional ultrasonic emitter  115  coupled to be driven by processing logic  201 . SLM  210  includes an infrared emitter  205 , an infrared light director  206  (illustrated in  FIG. 2C ), and a display pixel array  213 . Display pixel array  213  is a transmissive pixel array, in  FIG. 2A . 
     Processing logic  201  may include a processor, microprocessor, cluster of processing cores, FPGA (field programmable gate array), and/or other suitable combination of logic hardware. In some embodiments, memories (not illustrated) are integrated into the processing logic to store instructions to execute operations and/or store data. An external memory or memories (not illustrated) may also be coupled to processing logic  201  to store instructions to execute operations and/or store data. A “memory” or “memories” described in this disclosure may include volatile or non-volatile memory architectures. 
     With ultrasonic signal  117  focused on voxel  133  in diffuse medium  130 , IR illuminator  151  is selectively activated to emit general illumination emission  152  and a portion of emission  152  encounters voxel  133 . 
     In  FIG. 2B , the wavelength-shifted portion of the general illumination emission  152  is illustrated as shifted infrared imaging signal  243 . Being influenced by ultrasonic signal  117 , shifted infrared imaging signal  243  has a different wavelength (lambda-two) than general illumination emission  152  (lambda-one). 
     System  200  receives (at least a portion of) shifted signal  243 . An input optic  247  may optionally be included in system  200 . Input optic  247  may receive shifted signal  243  and focus the shifted signal  243  to be incident on image pixel array  270 . In one embodiment, input optic  247  is configured to filter out an angled portion of the shifted signal  243 , as described with regard to an embodiment of input optic  147 . 
     Still referring to  FIG. 2B , reference emitter  255  is configured to selectively emit an infrared reference light having the lambda-two wavelength so that infrared reference wavefront  257  interferes with the incoming shifted signal  243 . Reference emitter  255  may include one or more laser diodes and reference director optic  256  in optical structure  280  may direct the lambda-two infrared reference light to image pixel array  270  as a substantially uniform infrared reference wavefront  257 . Processing logic  201  is coupled to selectively activate reference emitter  255  via output X3, in the illustrated embodiment. 
     A linear polarizer is included in system  200  to polarize shifted signal  243  to have the same polarization orientation as infrared reference wavefront  257 . Reference emitter  255  may generate linear polarized light which imparts a polarization orientation to infrared reference wavefront  257 . The linear polarizer may be included in optic  247 , filter  273 , or optical structure  280 . 
       FIG. 3  illustrates an optic that may be used in the optical structure  280 , in accordance with an embodiment of the disclosure.  FIG. 3  includes a beam splitter  354  embedded in a light guide  356 . Reference emitter  255  is optically coupled to emit the infrared reference light into the light guide  356  along an optical path  358 . Infrared emitter  205  is optically coupled to emit an infrared wavefront into the opposite end of light guide  356  along an optical path  308 . Light guide  356  may be configured to confine the infrared light propagating in light guide  356  by Total Internal Reflection (TIR). However, the light reflecting off of beam splitter  354  may achieve the critical angle to be outcoupled from the light guide  356  as infrared wavefront  307  (toward display pixel array  213 ) or as infrared reference wavefront  357  (toward the image pixel array  270 ). Since beam splitter  354  still passes a portion of incident light, at least a portion of the shifted signal  243  will still reach image pixel array  270  when the configuration of  FIG. 3  is used in optical structure  280 . 
     In one embodiment (not illustrated), optical structure  280  includes a slim optic including a graduated gradient grating and the reference emitter is disposed to emit the infrared reference light at an edge of the graduated gradient grating. The graduated gradient grating is configured to increase a percentage of the infrared reference light as a distance from the edge of the graduated gradient grating increases to achieve a substantially uniform infrared reference wavefront  257 . In one embodiment, an electronically switchable hologram may be included in optical structure  280  and the electronically switchable hologram may be activated to direct the infrared reference wavefront  257  to image pixel array  270  when the reference emitter  255  is activated. Another electronically switchable hologram may be activated when infrared emitter  205  is activated to directed infrared light  207  to illuminate display pixel array  213 . 
     Returning again to  FIG. 2B , shifted signal  243  may encounter input optic  247 , display pixel array  213 , and optical structure  280  prior to becoming incident upon image pixel array  270 . The shifted signal  243  interferes with infrared reference wavefront  257  and image pixel array  270  captures an infrared image of the interference between shifted signal  243  and infrared reference wavefront  257 . To allow shifted signal  243  to pass through display pixel array  213 , each of the display pixels of the display pixel array  213  may be driven to a transmissive state while IR illuminator  151  and reference emitter  255  are activated. 
     In one embodiment, reference director optic  256  is configured to deliver the infrared reference wavefront  257  to the image pixel array  270  at an angle to a pixel plane of the image pixel array  270 . Processing logic  201  is coupled to initiate the image capture by image pixel array  270  via output X5, in the illustrated embodiment. 
     In the illustrated embodiment, an infrared filter  273  is disposed between optical structure  280  and image pixel array  270 . Infrared filter  273  may include the same configuration as infrared filter  173 . Image pixel array  270  may include the same configuration as image pixel array  170 . Image pixel array  270  is communicatively coupled to optical transform logic  250  to send the captured infrared image(s) to optical transform logic  250  for further processing. Optical transform logic  250  is coupled to image pixel array  270  via communication channel X7, in the illustrated embodiment. Optical transform logic  250  is coupled to receive the captured infrared image from the image pixel array  270  and provide a holographic pattern to be driven onto the display pixel array  213 . The optical transform logic  250  is configured to extract phase data of the interference captured by the infrared image and the holographic pattern is generated from the phase data. 
     Referring now to  FIG. 2C , display pixel array  213  is configured to generate an infrared holographic imaging signal  244  according to a holographic pattern driven onto the array  213 . Optical transform logic  250  is coupled to provide the array  213  the holographic pattern to array  213  via communication channel X8. 
     In  FIG. 2C , display pixel array  213  is illustrated as a transmissive LCD that is illuminated by infrared wavefront  207 . In the illustrated embodiment, infrared emitter  205  is coupled to be driven by output X4 of processing logic  201 . When processing logic  201  turns on (activates) IR emitter  205 , infrared light propagates into IR light director  206 . IR light director  206  redirects the infrared light toward display pixel array  213 . IR emitter  205  is an infrared laser diode that emits monochromatic infrared light, in one embodiment. 
     In the illustrated embodiment, processing logic  201  selectively activates infrared emitter  205  and infrared light director  206  directs the infrared light to illuminate display pixel array  213  as infrared wavefront  207  while the holographic pattern is driven onto array  213 . Infrared wavefront  207  is the same wavelength as infrared reference wavefront  257 . Processing logic  201  may deactivate reference emitter  255  while display pixel array  213  is being illuminated by infrared wavefront  207 . Processing logic  201  may be configured to drive the reference emitter  255  to emit the infrared reference wavefront  257  and initiate the infrared image capture by the image pixel array  270  while the reference emitter  255  and the infrared illuminator  151  are emitting the infrared reference wavefront  257  and the general illumination emission  152 , respectively. 
     Display pixel array  213  generates an infrared holographic imaging signal  244  when the holographic pattern is illuminated by infrared wavefront  207  and the infrared holographic imaging signal  244  exits system  200  as a reconstruction (in reverse) of the shifted signal  243  that entered system  200 . Reconstructed signal  244  follows (in reverse) whatever scattered path that shifted signal  243  took from voxel  133  to the display pixel array  213  so reconstructed signal  244  is essentially “focused” back onto voxel  133 . 
     Voxel  133  may absorb or scatter reconstructed signal  244  according to biological characteristics of voxel  133  and sensors may measure an exit signal  245  of the reconstructed signal  244  that encounters voxel  133 . System  200  may optionally include a sensor  190  coupled to processing logic  201  via an input/output X9 to initiate light measurement of exit signal  245  and pass the light measurement to processing logic  201 . Although exit signal  245  is illustrated as being directed to sensor  190 , the illustrated exit signal  245  is only a portion of the exit signal  245  that will be generated from signal  244  encountering voxel  133  and exit signal  245  will have many exit points from diffuse medium in addition to the illustrated portion of exit signal  245 . The sensors that measure this exit signal may simply measure the amplitude of the exit signal. In one embodiment, the image pixel array  270  is used to measure the amplitude and/or phase of exit signal  245 . The amplitude and/or phase of the exit signal  245  may be used to generate an image of diffuse medium  130 . A reconstructed signal  244  may be directed to voxel  133  multiple times (with multiple corresponding measurements of exit signal  245 ) so that biological changes in voxel  133  may be recorded over a time range. 
     System  200  may refocus directional ultrasonic emitter  115  to different voxels of diffuse medium  130  and repeat the processes disclosed herein to raster scan diffuse medium  130  in order to generate a three-dimensional image of diffuse medium  130 . Driving different holographic patterns onto display pixel array  213  gives display pixel array  213  the ability to generate steerable holographic infrared beams that can focus the reconstructed signal (e.g.  244 ) to different voxels in three-dimensional space to facilitate the raster scanning of diffuse medium  130 . 
     In one embodiment, processing logic  201  is configured to drive the reference emitter  255  to emit the infrared reference wavefront  257  and initiate the infrared image capture by the image pixel array  270  while the reference emitter  255  and the infrared illuminator  151  are emitting the infrared reference wavefront  257  and the general illumination emission  152 , respectively. 
     In system  200 , image pixel array  270  is disposed in a parallel plane to display pixel array  213 . However, in some embodiments, image pixel array  270  may be angled to increase the signal of interference between the infrared reference wavefront  257  and shifted signal  243 . In system  100 , image pixel array  170  is illustrated as being in a plane that is orthogonal to display pixel array  113 . However, in some embodiment, image pixel array  170  may be angled to increase the signal of interference between the infrared reference wavefront  157  and shifted signal  143 . 
       FIG. 4  illustrates an example placement of components of an imaging system  400  in relationship to a human head, in accordance with an embodiment of the disclosure.  FIG. 4  is a top-down view of a human head  405 . Imaging system  400  includes SLMs  210 A- 210 E and imaging modules  260 A- 260 E arranged as in system  200 , and directional ultrasonic emitters  115 A and  115 B. Of course, SLMs  110  and imaging modules  160  coupled also be used instead of SLMs  210  and imaging modules  260  in imaging system  400 .  FIG. 4  shows that SLM  110 A may generate multiple reconstructed infrared signals  444  that are directed to image different voxels  433  of the brain while the exit signals  445  are imaged by different imaging modules  160 . The other SLMs  110 B- 110 E may also send reconstructed infrared signals  444  (not illustrated) to each of imaging modules  160 A-E. Scientific literature suggests that the penetration depth of infrared light into tissue is around 10 cm so multiple SLMs  110  and imaging modules  160  may be needed to image the entire brain or other tissue. Although not illustrated, sensors  190  may also be placed around a diffuse medium such as human head  405  to measure the exit signals  445 . A wearable hat may include system  400  so that system  400  can be worn as a wearable, in some embodiments. Other wearables may also include all or part of system  400 . 
       FIG. 5  illustrates example optical transform logic  550  with dedicated processing pipelines  523  coupled between a tiled image pixel array  570  and a tiled display pixel array  510 , in accordance with an embodiment of the disclosure. Image pixel array  570  includes a plurality of image pixel tiles  563 . In the illustrated embodiment of  FIG. 5 , there are sixteen image pixel tiles  563 A- 563 P. Display pixel array  510  includes sixteen display tiles  513 A- 513 P. Optical transformation logic  550  includes dedicated parallel processing pipelines  523 . Each of the dedicated processing pipelines  523  is coupled between an image pixel tile  563  and a display tile  513 . In the illustrated embodiment, the dedicated processing pipelines have a one-to-one correspondence between the image pixel tile and the display pixel tile. Each dedicated processing pipeline  523  is coupled to receive tiled pixel data generated by one of the image pixel tiles  563 . Image pixel array  570 , display pixel array  510 , and optical transform logic  550  may be used as image pixel array  170 / 270 , display pixel array  113 / 213 , and optical transform logic  150 / 250 , respectively. Through extensive testing, Applicants have discovered that processing tiled portions of the image pixel array to generate tiled holograms to be driven onto display tiles significantly reduces the processing time and thus increases the time efficiency of optical transform logic. 
     Each image pixel tile  563  may have integer x columns and integer y rows and the integer x and the integer y are both powers of two. Therefore, a tiled portion of the infrared image captured by image pixel array  570  may include pixel data including integer x columns and integer y rows and the integer x and the integer y are both powers of two. The integer x and the integer y may be a same integer. By having the pixel data be in powers of two (e.g. 256 by 256), the processing of the pixel data is optimized for digital processing. 
       FIG. 6  illustrates example optical transform logic  650  coupled between an image pixel array and a display pixel array, in accordance with an embodiment of the disclosure. Each of the dedicated processing pipelines  523  in  FIG. 5  may utilize optical transform logic  650 . Optical transform logic  650  may be used to generate a holographic pattern for an entire display pixel array or optical transform logic  650  may be utilized to generate a tiled hologram from an image pixel tile where the tiled hologram is to be driven onto a display tile that is a portion of a display pixel array.  FIG. 6  illustrates the optical transform logic  650  being included in a dedicated processing pipeline (e.g. dedicated processing pipeline  523 ) for a tiled architecture, but those skilled in the art will recognize that optical transform logic  650  may also be used in non-tiled architectures. Optical transform logic  650  may be included in an ASIC (Application Specific Integrated-Circuit) that includes each of dedicated processing pipelines  523 . In one embodiment, a multicore processor is configured to allow each core of the processor to be a dedicated processing pipeline  523 . 
       FIG. 6  includes an image pixel array tile  612  having image pixels  617  arranged in integer number y rows and integer number x columns. Readout circuitry  614  is coupled to read the signal value from each image pixels  617  via bitlines  619 . Fourier transform engine  651  in logic  650  is coupled to receive the tiled infrared image  660  from readout circuitry  614 , in  FIG. 6 . Fourier transform engine generates a frequency domain infrared image  661  by performing a Fourier transform on the tiled infrared image  660  received from readout circuitry  614 . 
     Frequency filtering engine  653  is coupled to receive the frequency domain infrared image  661  from Fourier transform engine  651  and also coupled to receive mask  662 . Frequency filtering engine  653  is configured to multiply the frequency domain infrared image  661  with the mask  662  to generate a filtered frequency domain infrared image  663 . Mask  662  is designed to isolate the frequency of the shifted signal  143 / 243  for further processing. Mask  662  may include a matrix that includes ‘1’ values for the portion of the frequency domain infrared image  661  that corresponds to the lambda-two wavelength of shifted signal  143 / 243  and ‘0’ values for other portions of the frequency domain infrared image  661 . In one embodiment, mask  662  is a two-dimensional Gaussian filter. 
     Inverse Fourier transform engine  655  is coupled to receive the filtered frequency domain infrared image  663  from frequency filtering engine  653  and configured to generate a spatial domain infrared image  665  by performing an inverse Fourier transform on the filtered frequency domain infrared image  663 . 
     Phase extraction engine  657  is coupled to receive the spatial domain infrared image  665  and configured to extract phase data  667  from the spatial domain infrared image  665 . In one embodiment, a function similar to the angle function in MATLAB software (published by Mathworks® of Natick, Mass.) is utilized to extract phase data  667 . A phase value between −π and π may be generated to represent the phase data. That value may be rescaled to a value between 0 and 2π to make the value a positive value. 
     A scaling block  659  may also be included in logic  650  to receive the phase data  667  and scale the phase data by a scaling factor to generate scaled phase data  669 . The scaling factor may represent a sizing difference between display pixels of the display tiles and image sensor pixels of the image pixel tiles. 
     The phase data  667  (or optionally the scaled phase data  669 ) is then provided to drive circuitry  664  as a holographic pattern that can be illuminated to generate the reconstructed signal  144 / 244 . 
     In one embodiment, logic  650  includes a lens compensation engine (not illustrated). The lens compensation engine may be configured to multiply the phase data  667  with a lens compensation matrix that represents the lensing of optics of the system (e.g.  100 / 200 ) that logic  250  is included in. For example, viewing  FIGS. 2B and 2C , the lens compensation matrix for system  200  may represent the optical properties of display pixel array  213  add to the optical properties of optical structure  280  since signal  243  passes through input optic  247 , display pixel array  213 , and optical structure  280  before becoming incident on image pixel array  270  while signal  244  only encounters input optic  247  as signal  244  exits system  200 . 
       FIG. 7  illustrates a flow chart illustrating an example process  700  of executing an optical transformation, in accordance with an embodiment of the disclosure. The order in which some or all of the process blocks appear in process  700  should not be deemed limiting. Rather, one of ordinary skill in the art having the benefit of the present disclosure will understand that some of the process blocks may be executed in a variety of orders not illustrated, or even in parallel. The process blocks of process  700  may be executed by system  100 , system  200 , or devices using components from system  100  or  200 . 
     In process block  705 , an image sensor is illuminated with an infrared reference beam (e.g.  157 / 257 ). The infrared image may include pixel data including integer x columns and integer y rows. The integer x and the integer y may both be powers of two. Both the integer x and the integer y may be the same integer. 
     In process block  710 , an infrared image is captured with the image sensor while the infrared reference beam is illuminating the image sensor and the infrared image captures an interference between the infrared reference beam and an incoming infrared image signal (e.g.  143 / 243 ). 
     In process block  715 , a frequency domain infrared image (e.g.  661 ) is generated by performing a Fourier transform operation on the infrared image. Fourier transform engine  651  may perform process block  715 . 
     In process block  720 , a filtered frequency domain infrared image (e.g.  663 ) is generated by applying a mask (e.g.  662 ) to the frequency domain infrared image to isolate a frequency representing the interference between the infrared reference beam and the incoming infrared image signal. In one embodiment, applying the mask includes multiplying the frequency domain infrared image with a matrix including values of ones and zeros. The matrix may have integer x columns and the integer y rows that are the same integer x and y from process block  705 . In one embodiment, the mask is a two-dimensional Gaussian filter. Frequency filtering engine  653  may perform process block  720 . 
     In process block  725 , a spatial domain infrared image (e.g.  665 ) is generated by performing an inverse Fourier transform on the filtered frequency domain infrared image. Inverse Fourier transform engine  655  may perform process block  725 . 
     In process block  730 , phase data is extracted from the spatial domain infrared image. In one embodiment, extracting the phase data includes isolating an imaging number of a function representing the spatial domain infrared image. Phase extraction engine  657  may perform process block  730 . 
     In process block  735 , a hologram is generated with the phase data. 
     In process block  740 , a display (e.g. SLM  110 / 210 ) is illuminated with an infrared source to generate an infrared wavefront (e.g.  107 / 207 ). The infrared source (e.g.  205 ) has a same wavelength as the infrared reference beam. The hologram generated in process block  735  is driven onto the display while the display is illuminated to generate a reconstruction (e.g.  144 / 244 ) of the incoming infrared image signal. 
     In one embodiment, process  700  further includes apply a lensing adjustment to the phase data. The lensing adjustment may account for a lensing of components of a device encountered by the reconstruction of the incoming infrared image signal subsequent to exiting the display. In one embodiment of process  700 , the infrared reference beam is angled with respect a pixel plan of the image sensor. In one embodiment, process  700  further includes scaling the hologram by a scaling factor representing a sizing difference between display pixels of the display and image sensor pixels of the image sensor. In one embodiment, process  700  further includes scaling the hologram by a scaling factor representing a resolution difference between display pixels of the display and image sensor pixels of the image sensor. 
       FIGS. 8A-8B  illustrate an example imaging system that includes an image pixel array and extraction logic, in accordance with an embodiment of the disclosure. System  800  illustrated in  FIGS. 8A-8B  does not include a display pixel array, as in  FIGS. 1A-2C . In  FIG. 8A , processing logic  801  is coupled to drive directional ultrasonic emitter  115  to focus ultrasonic signal  117  to different locations in three-dimensional space, via output X1. Processing logic  801  is also coupled to selectively activate IR illuminator  151  via output X2, in the illustrated embodiment. System  800  may include a plurality of discrete devices that incorporate components of system  800 , in some embodiments. 
     Imaging module  860  includes image pixel array  870  and filter(s)  873 . In  FIG. 8A , imaging system  800  also includes a directional ultrasonic emitter  115  coupled to be driven by processing logic  801 . 
     Processing logic  801  may include a processor, microprocessor, cluster of processing cores, FPGA (field programmable gate array), and/or other suitable combination of logic hardware. In some embodiments, memories (not illustrated) are integrated into the processing logic to store instructions to execute operations and/or store data. An external memory or memories (not illustrated) may also be coupled to processing logic  801  to store instructions to execute operations and/or store data. A “memory” or “memories” described in this disclosure may include volatile or non-volatile memory architectures. 
     With ultrasonic signal  117  focused on voxel  133  in diffuse medium  130 , IR illuminator  151  is selectively activated to emit general illumination emission  152  and a portion of emission  152  encounters voxel  133 . 
     In  FIG. 8B , the wavelength-shifted portion of the general illumination emission  152  is illustrated as shifted infrared imaging signal  843 . Being influenced by ultrasonic signal  117 , shifted infrared imaging signal  843  has a different wavelength (lambda-two) than general illumination emission  152  (lambda-one). 
     System  800  receives (at least a portion of) shifted signal  843 . An input optic  847  may optionally be included in system  800 . Input optic  847  may receive shifted signal  843  and focus the shifted signal  843  to be incident on image pixel array  870 . In one embodiment, input optic  847  is configured to filter out an angled portion of the shifted signal  843 , as described with regard to an embodiment of input optic  147 . 
     Still referring to  FIG. 8B , reference emitter  855  is configured to selectively emit an infrared reference light having the lambda-two wavelength so that infrared reference wavefront  857  interferes with the incoming shifted signal  843 . Reference emitter  855  may include one or more laser diodes and reference director optic  856  in optical structure  880  may direct the lambda-two infrared reference light to image pixel array  870  as a substantially uniform infrared reference wavefront  857 . Processing logic  801  is coupled to selectively activate reference emitter  855  via output X3, in the illustrated embodiment. 
     Shifted signal  843  may encounter input optic  847  and optical structure  880  prior to becoming incident upon image pixel array  870 . The shifted signal  843  interferes with infrared reference wavefront  857  and image pixel array  870  captures an infrared image of the interference between shifted signal  843  and infrared reference wavefront  857 . In one embodiment, reference director optic  856  is configured to deliver the infrared reference wavefront  857  to the image pixel array  870  at an angle to a pixel plane of the image pixel array  870 . Processing logic  801  is coupled to initiate the image capture by image pixel array  870  via output X5, in the illustrated embodiment. 
     In the illustrated embodiment, an infrared filter  873  is disposed between optical structure  880  and image pixel array  870 . Infrared filter  873  may include the same configuration as infrared filter  173 . Image pixel array  870  may include the same configuration as image pixel array  170 . Image pixel array  870  is communicatively coupled to extraction logic  850  to send the captured infrared image(s) to extraction logic  850  for further processing. Extraction logic  850  is coupled to image pixel array  870  via communication channel X7, in the illustrated embodiment. Extraction logic  850  is coupled to receive the captured infrared image from the image pixel array  870  and configured to intensity data for incorporating into a composite image of diffuse medium  130 . 
     A linear polarizer is included in system  800  to polarize shifted signal  843  to have the same polarization orientation as infrared reference wavefront  857 . Reference emitter  855  may generate linear polarized light which imparts a polarization orientation to infrared reference wavefront  857 . The linear polarizer may be included in optic  847 , filter  873 , or optical structure  880 . 
       FIG. 9  illustrates an image pixel array  912  coupled to example extraction logic  950 , in accordance with an embodiment of the disclosure. Image pixel array  912  includes image pixels  917  arranged in integer number x columns and integer number y rows. Readout circuitry  914  is coupled to read the signal value from each image pixels  917  via bitlines  919 . Transform engine  951  in engine  950  is coupled to receive the tiled infrared image  960  from readout circuitry  914 , in  FIG. 9 . Transform engine  951  generates a frequency domain infrared image  961  by performing a Transform operation on the tiled infrared image  960  received from readout circuitry  914 . In one embodiment, the Transform operation includes an inverse Fourier transform. In one embodiment, the Transform operation includes a discrete cosine transform. 
     Frequency filtering engine  953  is coupled to receive the frequency domain infrared image  961  from Transform engine  951  and also coupled to receive mask  962 . Frequency filtering engine  953  is configured to multiply the frequency domain infrared image  961  with the mask  962  to generate a filtered frequency domain infrared image  963 . Mask  962  is designed to isolate the frequency of the shifted signal  843  for further processing. Mask  962  may include a matrix that includes ‘1’ values for the portion of the frequency domain infrared image  961  that corresponds to the lambda-two wavelength of shifted signal  843  and ‘0’ values for other portions of the frequency domain infrared image  961 . In one embodiment, mask  662  is a two-dimensional Gaussian filter. 
     Intensity extraction engine  957  is coupled to receive the filtered frequency domain infrared image  963  and configured to extract intensity data  967  from the filtered frequency domain infrared image  963 . In one embodiment, generating the intensity data  967  includes averaging intensity values of the filtered frequency domain infrared image  963 . In an embodiment where a Fourier transform is used as the transform operation in Transform engine  951 , the Fourier coefficients are extracted from filtered frequency domain infrared image  963  and a sum of the logarithm of the absolute value of the Fourier coefficients is calculated. The sum is then used as intensity data  967 . 
     Intensity extraction logic  950  incorporates the intensity data as a voxel value in a composite image  969 . Composite image  969  is illustrated as a three-dimensional image in  FIG. 9  and may be a three-dimensional image of diffuse medium. As described in this disclosure, the system  800  may raster scan through diffuse medium  130  (focusing on different voxels) to generate a three-dimensional image of diffuse medium. 
       FIG. 10  illustrates a flow chart illustrating an example process  1000  of optical imaging, in accordance with an embodiment of the disclosure. The order in which some or all of the process blocks appear in process  1000  should not be deemed limiting. Rather, one of ordinary skill in the art having the benefit of the present disclosure will understand that some of the process blocks may be executed in a variety of orders not illustrated, or even in parallel. The process blocks of process  1000  may be executed by system  800  or devices using components from system  800 . 
     In process block  1005 , an image sensor (e.g.  870 ) is illuminated with an infrared reference beam (e.g.  857 ). In process block  1010 , an infrared image is captured with the image sensor while the infrared reference beam is illuminating the image sensor and the infrared image captures an interference between the infrared reference beam and an incoming infrared image signal (e.g.  843 ). 
     In process block  1015 , a frequency domain infrared image (e.g.  961 ) is generated by performing a Transform operation on the infrared image. Transform engine  951  may perform process block  1015 . In one embodiment, the transformation operation includes an inverse Fourier transform. In one embodiment, the transformation operation includes a discrete cosine transform. 
     In process block  1020 , a filtered frequency domain infrared image (e.g.  963 ) is generated by applying a mask (e.g.  962 ) to the frequency domain infrared image to isolate a frequency representing the interference between the infrared reference beam and the incoming infrared image signal. In one embodiment, applying the mask includes multiplying the frequency domain infrared image with a matrix including values of ones and zeros. In one embodiment, the mask is a two-dimensional Gaussian filter. Frequency filtering engine  953  may perform process block  1020 . 
     In process block  1025 , intensity data is generated from the filtered frequency domain infrared image. In one embodiment, generating the intensity data includes averaging intensity values of the filtered frequency domain infrared image. In an embodiment where a Fourier transform is used as the transform operation in process block  1015 , the Fourier coefficients are extracted from filtered frequency domain infrared image and a sum of the logarithm of the absolute value of the Fourier coefficients is calculated. The sum is then used as intensity data. 
     In process block  1030 , intensity data is incorporated as a voxel value in a composite image. The composite image may be a three-dimensional composite image. Logic  950  may provide the three-dimensional composite image to a network, in some embodiment. 
     The processes explained above are described in terms of computer software and hardware. The techniques described may constitute machine-executable instructions embodied within a tangible or non-transitory machine (e.g., computer) readable storage medium, that when executed by a machine will cause the machine to perform the operations described. Additionally, the processes may be embodied within hardware, such as an application specific integrated circuit (“ASIC”) or otherwise. 
     A tangible non-transitory machine-readable storage medium includes any mechanism that provides (i.e., stores) information in a form accessible by a machine (e.g., a computer, network device, personal digital assistant, manufacturing tool, any device with a set of one or more processors, etc.). For example, a machine-readable storage medium includes recordable/non-recordable media (e.g., read only memory (ROM), random access memory (RAM), magnetic disk storage media, optical storage media, flash memory devices, etc.). 
     Communication channels described in this disclosure may include wired or wireless communications utilizing IEEE 802.11 protocols, BlueTooth, SPI (Serial Peripheral Interface), I 2 C (Inter-Integrated Circuit), USB (Universal Serial Port), CAN (Controller Area Network), cellular data protocols (e.g. 3G, 4G, LTE, 5G), or otherwise 
     The above description of illustrated embodiments of the invention, including what is described in the Abstract, is not intended to be exhaustive or to limit the invention to the precise forms disclosed. While specific embodiments of, and examples for, the invention are described herein for illustrative purposes, various modifications are possible within the scope of the invention, as those skilled in the relevant art will recognize. 
     These modifications can be made to the invention in light of the above detailed description. The terms used in the following claims should not be construed to limit the invention to the specific embodiments disclosed in the specification. Rather, the scope of the invention is to be determined entirely by the following claims, which are to be construed in accordance with established doctrines of claim interpretation.