Doc Code: TR.PROV
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`Document Description: Provisional Cover Sheet (5816)
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`Provisional Application for Patent Cover Sheet
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`This is a request for filing a PROVISIONAL APPLICATION FOR PATENT under 37 CFR 1.53(c)
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`lnventor(s)
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`Inventor I
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`Given Name
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`Middle Name Family Name City
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`State
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`Mohammed N.
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`Islam
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`Ann Arbor Ml
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`us
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`SHORT-WAVE INFRARED SUPER-CONTINUUM LASERS FOR EARLY
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`DETECTION OF DENTAL CARIES
`
`Title of Invention
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`Attorney Docket Number (if applicable) OMNI0102PRV
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`Customer Number
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`109543
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`The invention was made by an agency of the United States Government or under a contract with an agency of the United
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`States Government.
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`® No.
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`0 Yes, the name of the U.S. Government agency and the Government contract number are:
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`EFS - Web 1.0.1
`
`Petitioner Apple Inc. – Ex. 1017, cover p. 1
`
`

`

`Doc Code: TR.PROV
`Document Description: Provisional Cover Sheet (SB16)
`
`PTO/SB/16 (11-08)
`Approved for use through OS/31/201S. OMB 0851-0032
`U.S. Patent and Trademark Office: U .S. DEPARTMENT OF COMMERCE
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`Entity Status
`Appiicant ciaims smaii entity status under 37 CFR 1.27
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`® Yes, appiicant quaiifies for smaii entity status under 37 CFR 1.27
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`Signature
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`Please see 37 CFR 1.4(d) for the form of the signature.
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`Signature
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`/David S. Bir/
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`First Name
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`David
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`Last Name
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`Bir
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`Date (YYYY-MM-DD)
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`2012-12-31
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`Registration Number
`(If appropriate)
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`38383
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`the provisionai application.
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`EPS - Web 1.0.1
`
`Petitioner Apple Inc. – Ex. 1017, cover p. 2
`
`

`

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`
`Petitioner Apple Inc. – Ex. 1017, cover p. 3
`
`

`

`OMNI0102PRV
`
`SHORT-WAVE INFRARED SUPER-CONTINUUM LASERS FOR EARLY DETECTION OF
`DENTAL CARIES
`
`TECHNICAL FIELD
`
`This disclosure relates to lasers and light sources for healthcare, medical, dental, or
`[0001]
`bio-technology applications, including systems and methods for using near-infrared or short-wave
`
`infrared light sources for eai'ly detection of dental caries, often called cavities.
`
`BACKGROUND AND SUMMARY
`
`Dental care and the prevention of dental decay or dental caries has changed in the
`[0002]
`United States over the past several decades, due to the introduction of fluoride to drinking water, the
`use of fluoride dentifrices and rinses, application of topical fluoride in the dental office, and
`improved dental hygiene. Despite these advances, dental decay continues to be the leading cause of
`tooth loss. With the improvements over the past several decades, the majority of newly discovered
`carious lesions tend to be localized to the occlusal pits and fissures of the posterior dentition and the
`proximal contact sites. These early carious lesions may be often obscured in the complex and
`convoluted topography of the pits and fissures or may be concealed by debris that frequently
`accumulates in those regions of the posterior teeth. Moreover, such lesions are difficult to detect in
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`the early stages of development.
`
`Dental caries may be a dynamic disease that is characterized by tooth
`[0003]
`demineralization leading to an increase in the porosity of the enamel surface. Leaving these lesions
`untreated may potentially lead to cavities reaching the dentine and pulp and perhaps eventually
`causing tooth loss. Occlusal surfaces (bite surfaces) and approximal surfaces (between the teeth) are
`among the most susceptible sites of demineralization due to acid attack from bacterial by-products in
`the biofilm. Therefore, there is a need for detection of lesions at an early stage, so that preventive
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`agents may be used to inhibit or reverse the demineralization.
`
`Petitioner Apple Inc. – Ex. 1017, p. 1
`
`

`

`OMNI0102PRV
`
`[0004]
`
`Traditional methods for caries detection include visual examination and tactile
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`probing with a sharp dental exploration tool, often assisted by radiographic (x-ray) imaging.
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`However, detection using these methods may be somewhat subjective; and, by the time that caries
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`are evident under visual and tactile examination, the disease may have already progressed to an
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`advanced stage. Also, because of the ionizing nature of x-rays, they are dangerous to use (limited
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`use with adults, and even less used with children). Although x-ray methods are suitable for
`approximal surface lesion detection, they offer reduced utility for screening early caries in occlusal
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`surfaces due to their lack of sensitivity at very early stages of the disease.
`
`Some of the cuirent imaging methods are based on the observation of the changes of
`[0005]
`the light transport within the tooth, namely absoiption, scattering, transmission, reflection and/or
`fluorescence of light. Porous media may scatter light more than unifomi media. Taking advantage
`of this effect, the Fiber-optic trans-illumination is a qualitative method used to highlight the lesions
`within teeth by observing the patterns formed when white light, pumped from one side of the tooth,
`is scattered away and/or absorbed by the lesion. This technique may be difficult to quantify due to
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`an uneven light distribution inside the tooth.
`
`Another method called quantitative light-induced fluorescence - QLF - relies on
`[0P06]
`different fluorescence from solid teeth and caiies regions when excited with bright light in the
`visible. For example, when excited by relatively high intensity blue light, healthy tooth enamel
`yields a higher intensity of fluorescence than does demineralized enamel that has been damaged by
`caries infection or any other cause. On the other hand, for excitation by relatively high intensity of
`red light, the opposite magnitude change occurs, since this is the region of the spectrum for which
`bacteria and bacterial by-products in carious regions absorb and fluoresce more pronouncedly than
`do healthy areas. However, the image provided by QLF may be difficult to assess due to relatively
`poor contrast between healthy and infected ai'eas.
`Moreover, QLF may have difficulty
`discriminating between white spots and stains because both produce similar effects. Stains on teeth
`are commonly obsewed in the occlusal sites of teeth, and this obscures the detection of caries using
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`visible light.
`
`Petitioner Apple Inc. – Ex. 1017, p. 2
`
`

`

`OMNI0102PRV
`
`[0007]
`
`As described in this disclosure, the near-infrared region of the spectrum offers a novel
`
`approach to imaging carious regions because scattering is reduced and absorption by stains is low.
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`For example, it has been demonstrated that the scattering by enamel tissues reduces in the form of
`l/(wavelength)^, e.g., inversely as the cube of wavelength. By using a broadband light source in the
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`short-wave infrared (SWIR) part of the spectrum, which corresponds approximately to 1400nm to
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`2500nm, lesions in the enamel and dentine may be observed. In one embodiment, intact teeth have
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`low reflection over the SWIR wavelength range. In the presence of caries, the scattering increases,
`and the scattering is a function of wavelength; hence, the reflected signal decreases with increasing
`wavelength. Moreover, paiticularly when caries exist in the dentine region, water build up may
`occur, and dips in the SWIR spectrum corresponding to the water absorption lines may be observed.
`
`The scattering and water absorption as a function of wavelength may thus be used for early detection
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`of caries and for quantifying the degree of demineralization.
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`SWIR light may be generated by light sources such as lamps, light emitting diodes,
`[0008]
`one or more laser diodes, super-luminescent laser diodes, and fiber-based super-continuum sources.
`The SWIR super-continuum light sources advantageously may produce high intensity and power, as
`well as being a nearly transfomi-limited beam that may also be modulated. Also, apparatuses for
`caries detection may include C-clamps over teeth, a handheld device with light input and light
`detection, which may also be attached to other dental equipment such as drills. Alternatively, a
`mouth-guard type appai-atus may be u.sed to simultaneously illuminate one or more teeth. Fiber
`optics may be conveniently used to guide the light to the patient as well as to transport the signal
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`back to one or more detectors and receivers.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`For a more complete understanding of the present disclosure, and for further features
`[0009]
`and advantages thereof, reference is now made to the following description taken in conjunction
`
`with the accompanying drawings, in which:
`
`[0010]
`
`FIGURE 1 illustrates the structure of a tooth.
`
`Petitioner Apple Inc. – Ex. 1017, p. 3
`
`

`

`OMNI0102PRV
`
`[0011]
`
`FIGURE 2A shows the attenuation coefficient for dental enamel and water versus
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`wavelength from approximately 600nm to 2600nm.
`
`[0012]
`
`FIGURE 2B illustrates the absorption spectrum of intact enamel and dentine in the
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`wavelength range of approximately 1.2 to 2.4 microns.
`
`[0013]
`
`FIGURE 3 shows the near infrared spectral reflectance over the wavelength range of
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`approximately 800nm to 2500nm from an occlusal tooth surface. The black diamonds correspond to
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`the reflectance from a sound, intact tooth section. The asterisks correspond to a tooth section with
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`an enamel lesion. The circles correspond to a tooth section with a dentine lesion.
`
`[0014]
`
`FIGURE 4 illustrates a hand-held dental tool design of a human interface that may
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`also be coupled with other dental tools.
`
`[0015]
`
`FIGURE 5 illustrates a clamp design of a human interface to cap over one or more
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`teeth and perform a non-invasive measurement for dental caries.
`
`[0016]
`
`FIGURE 6 shows a mouth guard design of a human interface to perform a non-
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`invasive measurement for dental caries.
`
`[0017]
`
`FIGURE 7 illustrates a block diagram or building blocks for constructing high power
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`laser diode assemblies.
`
`FIGURE 8 shows a platform architecture for different wavelength ranges for an all-
`[0018]
`fiber-integrated, high powered, super-continuum light source.
`
`[0019]
`
`FIGURE 9 illustrates one embodiment for a short-wave infrared super-continuum
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`light source.
`
`FIGURE 10 shows the output spectmm from the SWIR SC laser of FIGURE 9 when
`[0020]
`about I Cm length of fiber for SC generation is used. This fiber is a single-mode, non-dispersion
`
`shifted fiber that is optimized for operation near 1550nm.
`
`Petitioner Apple Inc. – Ex. 1017, p. 4
`
`

`

`OMNI0102PRV
`
`[0021]
`
`FIGURE 11 shows the output spectrum from the SWIR SC laser of FIGURE 9 when
`
`about 2m length of fiber for SC generation is used. This fiber is a single-mode, non-dispersion
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`shifted fiber that is optimized for operation near 1550nm.
`
`[0022]
`
`FIGURE 12 illustrates high power SWIR-SC lasers that may generate light between
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`approximately 1.4-1.8 microns (top) or approximately 2-2.5 microns (bottom).
`
`[0023]
`
`FIGURE 13 schematically shows that the medical measurement device can be part of
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`a personal or body area network that communicates with another device (e.g., smart phone or tablet)
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`that communicates with the cloud. The cloud may in turn communicate information with the user,
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`dental or healthcare providers, or other designated recipients.
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`DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS
`
`[0024]
`
`As required, detailed embodiments of the present disclosure are disclosed herein;
`
`however, it is to be understood that the disclosed embodiments are merely exemplary of the
`disclosure that may be embodied in various and alternative forms. The figures are not necessarily to
`scale; some features may be exaggerated or minimized to show details of particular components.
`Therefore, specific stnjctural and functional details disclosed herein are not to be interpreted as
`limiting, but merely as a representative basis for teaching one .skilled in the ait to variously employ
`
`the present disclosure.
`
`Near-infrared (NIR) and SWIR light may be prefeiTed for caries detection compared
`[0025]
`to visible light imaging because the NIR/SWIR wavelengths generally have lower absorption by
`stains and deeper penetration into teeth. Hence, NIR/SWIR light may provide a caries detection
`
`method that can be non-invasive, non-contact and relatively stain insensitive. Broadband light may
`provide further advantages because carious regions may demonstrate spectral signatures from water
`absorption and the wavelength dependence of porosity in the scattering of light.
`
`In general, the near-infrared region of the electromagnetic spectrum covers between
`[0026]
`approximately 0.7 microns (700nm) to about 2.5 microns (2500nm). However, it may also be
`advantageous to use just the short-wave infrared between approximately 1.4 microns (I400nm) and
`
`Petitioner Apple Inc. – Ex. 1017, p. 5
`
`

`

`OMNI0102PRV
`
`about 2.5 microns (2500nm). One reason for preferring the SWIR over the entire NIR may be to
`
`operate in the so-called "eye safe" window, which corresponds to wavelengths longer than about
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`1400nm. Therefore, for the remainder of the disclosui-e the SWIR will be used for illustrative
`
`purposes. However, it should be clear that the discussion that follows could also apply to using the
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`NIR wavelength range, or other wavelength bands.
`
`[0027]
`In particular, wavelengths in the eye safe window may not transmit down to the retina
`of the eye, and therefore, these wavelengths may be less likely to create permanent eye damage from
`inadvertent exposure. The near-infrared wavelengths have the potential to be dangerous, because the
`eye cannot see the wavelengths (as it can in the visible), yet they can penetrate and cause damage to
`the eye. Even if a practitioner is not looking directly at the laser beam, the practitioner's eyes may
`receive stray light from a reflection or scattering from some surface. Hence, it can always be a good
`practice to use eye protection when working around lasers. Since wavelengths longer than about
`1400nm are substantially not transmitted to the retina or substantially absorbed in the retina, this
`wavelength range is known as the eye safe window. For wavelengths longer than 1400nm, in
`general only the cornea of the eye may receive or absorb the light radiation.
`
`FIGURE 1 illustrates the stmcture of an exemplaj-y cross-section of a tooth 100. The
`[0028]
`tooth 100 has a top layer called the crown 101 and below that a root 102 that reaches well into the
`gum 106 and bone 108 of the mouth. The exterior of the crown 101 is an enamel layer 103, and
`below the enamel is a layer of dentine 104 that sits atop a layer of cementum 107. Below the dentine
`104 is a pulp region 105, which comprises within it blood vessels 109 and nerves 110. If the light
`can penetrate the enamel 103 and dentine 104, then the blood flow and blood constituents may be
`measured through the blood vessels in the dental pulp 105. While the amount of blood flow in the
`capillaries of the dental pulp 105 may be less than an ailery or vein, the smaller blood flow could
`still be advantageous for detecting or measuring blood constituents as compared to detection through
`the skin if there is less interfering spectral features from the tooth.
`
`[0029]
`
`As used throughout this document, the term "couple" and or "coupled" refers to any
`
`direct or indirect communication between two or more elements, whether or not those elements are
`physically connected to one another. As used throughout this disclosure, the term spectroscopy
`
`Petitioner Apple Inc. – Ex. 1017, p. 6
`
`

`

`OMNI0102PRV
`
`means that a tissue or sample is inspected by comparing different features, such as wavelength (or
`
`frequency), spatial location, transmission, absorption, reflectivity, scattering, refractive index, or
`
`opacity. In one embodiment, "spectroscopy" may mean that the wavelength of the light source is
`
`varied, and the transmission, absorption, or reflectivity of the tissue or sample is measured as a
`
`function of wavelength. In another embodiment, "spectroscopy" may mean that the wavelength
`
`dependence of the transmission, absoiption or reflectivity is compared between different spatial
`
`locations on a tissue or sample. As an illustration, the "spectroscopy" may be performed by varying
`
`the wavelength of the light source, or by using a broadband light source and analyzing the signal
`
`using a spectrometer, wavemeter, or optical spectmm analyzer.
`
`[0030]
`As used throughout this disclosure, the term "fiber laser" refers to a laser or oscillator
`that has as an output light or an optical beam, wherein at least a part of the laser comprises an optical
`
`fiber. For instance, the fiber in the "fiber laser" may comprise one of or a combination of a single
`
`mode fiber, a multi-mode fiber, a mid-infrared fiber, a photonic crystal fiber, a doped fiber, a gain
`
`fiber, or, more generally, an approximately cylindrically shaped waveguide or light-pipe. In one
`embodiment, the gain fiber may be doped with rare earth material, such as ytterbium, erbium, and/or
`thulium, for example. In another embodiment, the mid-infrared fiber may comprise one or a
`combination of fluoride fiber, ZBLAN fiber, chalcogenide fiber, tellurite fiber, or germanium doped
`fiber. In yet another embodiment, the single mode fiber may include standard single-mode fiber,
`dispersion shifted fiber, non-zero dispersion shifted fiber, high-nonlinearity fiber, and small core size
`
`fibers.
`
`As used throughout this disclosure, the term "pump laser" refers to a laser or
`[0031]
`oscillator that has as an output light or an optical beam, wherein the output light or optical beam is
`coupled to a gain medium to excite the gain medium, which in turn may amplify another input
`optical signal or beam. In one particular example, the gain medium may be a doped fiber, such as a
`fiber doped with ytterbium, erbium, and/or thulium. In one embodiment, the "pump laser" may be a
`fiber laser, a solid state laser, a laser involving a nonlinear crystal, an optical parametric oscillator, a
`semiconductor laser, or a plurality of semiconductor lasers that may be multiplexed together. In
`another embodiment, the "pump laser" may be coupled to the gain medium by using a fiber coupler.
`
`Petitioner Apple Inc. – Ex. 1017, p. 7
`
`

`

`OMNI0102PRV
`
`a dichroic mirror, a multiplexer, a wavelength division multiplexer, a grating, or a fiised fiber
`
`coupler.
`
`[0032]
`
`As used throughout this document, the term "super-continuum" and or
`
`"supercontinuum" and or "SC" refers to a broadband light beam or output that comprises a plurality
`
`of wavelengths. In a particular example, the plurality of wavelengths may be adjacent to one-
`
`another, so that the spectrum of the light beam or output appears as a continuous band when
`
`measured with a spectrometer. In one embodiment, the broadband light beam may have a bandwidth
`
`or at least lOnm. In another embodiment, the "super-continuum" may be generated through
`nonlinear optical interactions in a medium, such as an optical fiber or nonlinear crystal. For
`example, the "super-continuum" may be generated through one or a combination of nonlinear
`activities such as four-wave mixing, the Raman effect, modulational instability, and self-phase
`
`modulation.
`
`As used throughout this disclosure, the terms "optical light" and or "optical beam"
`[0033]
`and or "light beam" refer to photons or light transmitted to a particular location in space. The
`"optical light" and or "optical beam" and or "light beam" may be modulated or unmodulated, which
`also means that they may or may not contain information. In one embodiment, the "optical light"
`and or "optical beam" and or "light beam" may originate from a fiber, a fiber laser, a laser, a light
`emitting diode, a lamp, a pump laser, or a light source.
`
`TRANSMISSION OR REFLECTION THROUGH TEETH
`
`The transmission, absoi-ption and reflection from teeth has been studied in the near
`[0034]
`infrared, and, although there are some features, the enamel and dentine appear to be fairly
`transparent in the near infrared (particularly SWIR wavelengths between about 1400 and 2500nm).
`For example, the absorption or extinction ratio for light transmission has been studied. FIGURE 2A
`illustrates the attenuation coefficient 200 for dental enamel 201 (filled circles) and the absorption
`coefficient of water 202 (open circles) versus wavelength. Near-infrared light may penetrate much
`further without scattering through all the tooth enamel, due to the reduced scattering coefficient in
`normal enamel. Scattering in enamel may be fairly strong in the visible, but decreases as
`
`Petitioner Apple Inc. – Ex. 1017, p. 8
`
`

`

`OMNI0102PRV
`
`approximately [/(wavelength)^ [i.e., inver.se of the cube of the wavelength] with increasing
`
`wavelength to a value of only 2-3 cm-1 at 1310nm and 1550nm in the near infrared. Therefore,
`
`enamel may be virtually transparent in the near infrared with optical attenuation 1-2 orders of
`
`magnitude less than in the visible range.
`
`[0035]
`
`As another example, FIGURE 2B illustrates the absorption spectrum 250 of intact
`
`enamel 251 (dashed line) and dentine 252 (solid line) in the wavelength range of approximately 1.2
`
`to 2.4 microns. In the near infrared there are two absorption bands in the areas of about 1.5 and 2
`
`microns. The band with a peak around 1.57 microns may be attributed to the overtone of valent
`vibration of water present in both enamel and dentine. In this band, the absorption is greater for
`
`dentine than for enamel, which may be related to the large water content in this tissue. In the region
`
`of 2 microns, dentine may have two absorption bands, and enamel one. The band with a maximum
`near 2.1 microns may belong to the overtone of vibration of PO hydroxyapatite groups, which is the
`
`main substance of both enamel and dentine. Moreover, the band with a peak near 1.96 microns in
`dentine may correspond to water absorption (dentine may contain substantially higher water than
`
`enamel).
`
`In addition to the absorption coefficient, the reflectance from intact teeth and teeth
`[0036]
`with dental caries (e.g., cavities) has been studied. In one embodiment, FIGURE 3 shows the near
`infrared spectral reflectance 300 over the wavelength range of approximately 800nm to 2500nm
`from an occlusal (e.g., top) tooth surface 304. The curve with black diamonds 301 corresponds to
`the reflectance from a sound, intact tooth section. The curve with asterisks (*) 302 corresponds to a
`
`tooth section with an enamel lesion. The curve with circles 303 corresponds to a tooth section with a
`dentine lesion. Thus, when there is a lesion, more scattering occurs and there may be an increase in
`
`the reflected light.
`
`For wavelengths shorter than approximately 1400nm, the shapes of the spectra remain
`[0037]
`similai", but the amplitude of the reflection changes with lesions. Between approximately 1400nm
`and 2500nm, an intact tooth 301 has low reflectance (e.g., high transmission), and the reflectance
`appeal's to be more or less independent of wavelength. On the other hand, in the presence of lesions
`302 and 303, there is increased scattering, and the scattering loss may be wavelength dependent. For
`
`Petitioner Apple Inc. – Ex. 1017, p. 9
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`

`OMNI0102PRV
`
`example, the scattering loss may decrease as the inverse of some power of wavelength, such as
`l/(wavelength)^ -- so, the scattering loss decreases with longer wavelengths. When there is a lesion
`
`in the dentine 303, more water can accumulate in the area, so there is also increased water
`
`absorption. For example, the dips near 1450nm and 1900nm may correspond to water absorption,
`
`and the reflectance dips are pai ticulai'ly pronounced in the dentine lesion 303.
`
`[0038]
`
`FIGURE 3 may point to several novel techniques for early detection and
`
`quantification of carious regions. One method may be to use a relatively narrow wavelength range
`
`(for example, from a laser diode or super-luminescent laser diode) in the wavelength window below
`
`1400nm. In one embodiment, wavelengths in the vicinity of 1310nm may be used, which is a
`
`standard telecommunications wavelength where appropriate light sources are available. Also, it may
`be advantageous to use a super-luminescent laser diode rather than a laser diode, because the broader
`bandwidth may avoid the production of laser speckle that can produce interference patterns due to
`light's scattering after striking irregular surfaces. As FIGURE 3 shows, the amplitude of the
`reflected light (which may also be proportional to the inverse of the transmission) may increase with
`dental caries. Hence, comparing the reflected light from a known intact region with a suspect region
`may help identify carious regions. However, one difficulty with using a relatively narrow
`wavelength range and relying on amplitude changes may be the calibration of the measurement. For
`example, the amplitude of the reflected light may depend on many factors, such as irregularities in
`the dental surface, placement of the light source and detector, distance of the measurement
`
`instrument from the tooth, etc.
`
`In one embodiment, use of a plurality of wavelengths can help to better calibrate the
`[0039]
`dental caries measurement. For example, a plurality of laser diodes or super-luminescent laser
`diodes may be used at different center wavelengths. Alternately, a lamp or alternate broadband light
`source may be used followed by appropriate filters, which may be placed after the light source or
`before the detectors. In one example, wavelengths near 1090nm, 1440nm and 1610nm may be
`employed. The reflection from the tooth 305 appears to reach a local maximum near 1090nm in the
`representative embodiment illustrated. Also, the reflectance near 1440nm 306 is higher for dental
`caries, with a distinct dip particularly for dentine caiies 303. Near 16I0nm 307, the reflection is also
`higher for carious regions. By using a plurality of wavelengths, the values at different wavelengths
`
`10
`
`Petitioner Apple Inc. – Ex. 1017, p. 10
`
`

`

`OMNI0102PRV
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`may help quantify a caries score. In one embodiment, the degree of enamel lesion