Abstract: An inspection device includes: an illumination device that irradiates standard and inspection objects with near-infrared light; a spectroscope that disperses reflected light; an imaging device that takes images of first and second optical spectrums of the reflected light dispersed by the spectroscope to obtain standard spectroscopic image data and inspection spectroscopic image data; and a processor. The processor executes a predetermined arithmetic operation with regard to at least one of (i) each pixel row of the standard spectroscopic image data perpendicular to a wavelength dispersion direction and (ii) each pixel column of the standard spectroscopic image data parallel to the wavelength dispersion direction. The processor, based on luminance values of pixels belonging to the pixel row or column, determines a characteristic of the pixel row and grasps a wavelength sensitivity characteristic of the imaging element under the near-infrared light emitted from the illumination device.

Abstract: The invention relates to a sensor device for examining the coating of a disc as part of a coating process. The sensor device comprises a first optical sensor system for determining the layer thickness of the coating applied to the disc, and comprises a rotation apparatus. The invention is characterized in that the first optical sensor system is designed to simultaneously identify at least one first position-based measured value and one second position-based measured value, the first and the second position-based measured value describing the distance between the sensor systems and the surface of the disc. As a result of this, the sensor system is configured such that the first position-based measured value of a coated region of the disc and the second position-based measured value of an uncoated region of the disc are identified. Furthermore, the first optical sensor system comprises at least one linear guide, which extends from the central region to the edge.

Abstract: According to aspects of the embodiments, there is provided a method of measuring the amount of fountain solution employed in a digital offset lithography printing system. Fountain solution thickness is measured using a glass roll at a lower temperature than the fountain solution. The lower temperature causes the fountain solution to undergo a change in state and in a solid state the fountain solution crystalizes and changes roll opacity with the thickness of the film. When radiated with a light source the opacity is continuously measured through the surface of the roller. The thickness of the crystallized fountain solution can then be determined via the opacity level increase by the crystallization and the impact to the opacity on the glass roll.

Abstract: A multi-shield plate includes a plate having a substantially flat upper surface and a substantially flat lower surface, a plurality of first windows formed in the plate and extending through the plate from the upper surface to the lower surface, and a plurality of vapor shields mounted to the plate, each vapor shield of the plurality of vapor shields configured to prevent passage of a vapor through a corresponding window of the plurality of windows. The multi-shield plate includes an aperture formed in the plate, the aperture aligned with a first window of the plurality of windows along an axis corresponding to the upper surface.

Abstract: A blister packaging machine includes: a pocket portion forming unit that forms a pocket portion having a bottom portion and a side portion, in a belt-like container film, and adjusts balance between a thickness of the bottom portion and a thickness of the side portion; an illumination device that is disposed on a downstream side of the pocket portion forming unit, and irradiates the pocket portion with an electromagnetic radiation; an imaging device that is disposed on a side opposite to the illumination device across the container film, and obtains transmitted image data based on the electromagnetic radiation transmitted through the pocket portion; a side portion state detector that detects a state of the thickness of the side portion based on the transmitted image data; and a controller that controls an operation of the pocket portion forming unit.

Abstract: A method and apparatus is provided to inspect coverage of a coating applied to a surface of a component. A coating color space value of a color of the coating is obtained based on a camera, a light source, and the surface, each value having an associated coating thickness applied to the surface. Images of the coating covered surface are obtained. Each image is processed by determining color space values of the image, determining whether the associated coating thickness of the color space values is within a specified tolerance of a required thickness of coating based on a comparison of the color space values to color space values associated with the required thickness of coating, and responsive to the associated thickness of coating of the color space values being outside of the specified tolerance, providing an indication that the surface shown in the image is outside of the specified tolerance.

Abstract: Provided is an ellipsometer including a polarizing optical device configured to separate light, reflected from a sample that is irradiated with illumination light comprising a linearly polarized light, into a first linearly polarized light in a first polarization direction and a second linearly polarized light in a second polarization direction that is orthogonal to the first polarization direction, and a light-receiving optical system configured to calculate an ? and ?, an amplitude ratio and a phase difference of the two polarized light respectively, from an interference fringe formed by interference between the first linearly polarized light and the second linearly polarized light after passing through an analyzing device with transmission axis different from the first polarization direction and the second polarization direction.

Abstract: A multi-shield plate includes a plate having a substantially flat upper surface and a substantially flat lower surface, a plurality of first windows formed in the plate and extending through the plate from the upper surface to the lower surface, and a plurality of vapor shields mounted to the plate, each vapor shield of the plurality of vapor shields configured to prevent passage of a vapor through a corresponding window of the plurality of windows. The multi-shield plate includes an aperture formed in the plate, the aperture aligned with a first window of the plurality of windows along an axis corresponding to the upper surface.

Abstract: A signal waveform of an estimation signal and a signal waveform of the reflected light intensity signal are coordinated with each other such that a time point when a film thickness is equal to zero in the signal waveform of the estimation signal and a base point in the signal waveform of the reflected light intensity signal coincide with each other. A film thickness corresponding to that estimated value of a signal intensity of a reflected light which corresponds to a film thickness range corresponding to a time range in the signal waveform of the estimation signal and coincides with the signal intensity of the reflected light at a desired time point is set as a film thickness of a thin film at the desired time point.

Abstract: A vapor phase growth rate measuring apparatus has an initial parameter setting adjuster to set initial values of fitting parameters, a refractive index of each thin film to be formed on the substrate, a growth rate of each thin film, and at least one parameter having temperature dependence, a film thickness calculator to calculate a film thickness of each thin film, a parameter selector to select a value in accordance with a growth temperature for the parameter, a reflectometer to measure a reflectance of the substrate, a reflectance calculator to calculate a reflectance of the substrate, an error calculator to calculate an error between the calculated reflectance and an actual measurement value of the reflectance measured at a plurality of times, a parameter changer to change at least a part of the values of the fitting parameters, and an output value generator to generate characteristic values of each thin film.

Abstract: A solution for measuring a suspension which contains wood fibres. The consistency of the suspension is changed in a consistency range. Optical radiation is directed at the suspension and the intensity of optical radiation interacted with the suspension is measured at different consistencies in the consistency range. The maximum intensity of the optical radiation is determined within the consistency range. At least one of the following properties of the suspension are determined based on the determined maximum intensity: kappa number, brightness.

Abstract: A method for thickness measurement includes forming an implantation region in a semiconductor substrate. A semiconductor layer is formed on the implantation region of the semiconductor substrate. Modulated free carriers are generated in the implantation region of the semiconductor substrate. A probe beam is provided on the semiconductor layer and the implantation region of the semiconductor substrate with the modulated free carriers therein. The probe beam reflected from the semiconductor layer and the implantation region is detected to determine a thickness of the semiconductor layer.

Abstract: An analytical system includes a laser disposed to direct light toward a microfluidic feature disposed in a feature layer of a multiple layer test cartridge, a sensor to receive reflections from capping layers disposed about the microfluidic feature in the feature layer, and a controller to determine a depth of the microfluidic feature as a function of the received reflections.

Abstract: A semiconductor device manufacturing method includes forming a silicon layer by epitaxial growth over a semiconductor substrate having a first area and a second area; forming a first gate oxide film by oxidizing the silicon layer; removing the first gate oxide film from the second area, while maintaining the first gate oxide film in the first area; thereafter, increasing a thickness of the first gate oxide film in the first area and simultaneously forming a second gate oxide film by oxidizing the silicon layer in the second area; and forming a first gate electrode and a second gate electrode over the first gate oxide film and the second gate oxide film, respectively, wherein after the formation of the first and second gate electrodes, the silicon layer in the first area is thicker than the silicon layer in the second area.

Abstract: In the dihedral sensor system, two flat plates are secured to a dihedron so that the distance (L) between the edge and the meniscus and the spacing between the plates (a) on the meniscus will be a function of the dihedron tangent (?). Thus, for pure water the tension (?) is equal to the potential (T) and given by T=?2?/[L tg(?)], wherein ? is the water surface tension. In order to measure water tension in the soil, the system is coupled to porous elements, while the sensor edge is pressed directly against roots and other plant organs. Water potential, instead, is measured with the edge positioned at a few micrometers from the sample and the response takes place after the exchange of a few picoliters of water, when the condition of balance of temperature and water vapor is approached. Visually, with a sliding gauge, one measures water tensions between zero and 0.3 MPa, while with the aid of a microscope the reading extends up to 3.0 MPa. The water activity corresponding to water potentials lower than ?3.

Abstract: A light sensor-containing apparatus for detecting the thickness of inserts placed within a mailer including a picker arm, movable picker jaw that pivots during an insert gripping process, a target plate having a light reflective surface and secured to the picker arm end that moves when gripping an insert, and a light sensor mounted to the picker arm that emits a light beam and receives a reflected light beam that is reflected back from the light reflective surface to establish the thickness of the insert as controlled by associated computer programming is presented.

Abstract: A method and device for measuring a height of a microscopic structure such as solder bumps. For simplicity of explanation, the invention is described with respect to phase information and amplitude information wherein phase detection and calculation algorithms are being used.

Abstract: A method and system provide for depositing a TCO, transparent conductive oxide, film in one chamber of a manufacturing tool then irradiating the TCO film with light energy in another chamber of the same tool. The TCO film is used in a solar cell and formed on a solar cell substrate in some embodiments. The method includes irradiating the TCO film for a time and energy to reduce resistance of the TCO film without reducing transmittance. One or multiple light sources are used in the light irradiation chamber. Light in the infrared range, visible light range and ultraviolet light range are used either individually or in combination.

Abstract: A lithographic mask has a substrate substantially transmissive for radiation of a certain wavelength, the substrate having a radiation absorbing material in an arrangement, the arrangement configured to apply a pattern to a cross-section of a radiation beam of the certain wavelength, wherein the absorbing material has a thickness which is substantially equal to the certain wavelength divided by a refractive index of the absorbing material.

Abstract: A polishing apparatus capable of achieving a highly-precise polishing result is disclosed. The polishing apparatus includes an in-line film-thickness measuring device configured to measure a film thickness of the substrate in a stationary state, and an in-situ spectral film-thickness monitor having a film thickness sensor disposed in a polishing table, the in-situ spectral film-thickness monitor being configured to subtract an initial film thickness, measured by the in-situ spectral film-thickness monitor before polishing of the substrate, from an initial film thickness, measured by the in-line film-thickness measuring device before polishing of the substrate, to determine a correction value, add the correction value to a film thickness that is measured when the substrate is being polished to obtain a monitoring film thickness, and monitor a progress of polishing of the substrate based on the monitoring film thickness.

Abstract: Provided are a transparent substrate monitoring apparatus and a transparent substrate monitoring method. The transparent substrate monitoring apparatus includes a light emitting unit emitting light; a double slit disposed on a plane defined in a first direction and a second direction intersecting a propagation direction of incident light and includes a first slit and a second slit spaced apart from each other in the first direction to allow the light to pass therethrough; an optical detection unit measuring an intensity profile or position of an interference pattern formed on a screen plane; and a signal processing unit receiving a signal from the optical detection unit to calculate an optical phase difference or an optical path difference.

Abstract: An optical film thickness measuring device, enabling direct measurement of a film thickness of a product in real time accurately without a monitor substrate, includes: a projector, a light receiver, inner beam splitters disposed in a base substrate holder to reflect a measurement beam to a base substrate, an inner optical reflector that totally reflects a measurement beam from the closest inner beam splitter, external beam splitters the measurement beam from the inner beam splitters toward the light receiver, and an outer optical reflector that reflects the measurement beam from the optical reflector toward the light receiver. The measurement beam reflected by the inner beam splitters and the inner optical reflector is passed through the base substrate and then reflected by the external beam splitters and the outer optical reflector to be guided to the light receiver, so that the measurement beam is received by the light receiver.

Abstract: An apparatus arranged to analyze a multi-layer optical material structure, the apparatus constituted of: a control unit, a light source outputting light; and a light receiver arranged to receive the light from the light source after interaction with the target structure, the control unit arranged to: detect the amplitude of the received light as a function of wavelength; perform a transform of a function of the detected amplitudes to the optical thickness domain; determine, responsive to a planned composition of the target multi-layer structure, optical thickness and amplitude of expected peaks of the performed transform to the optical thickness domain which correspond with interactions with single interface between layers; identify actual peaks of the performed transform to the optical thickness domain which correspond with interfaces between layers; and determine at least one physical characteristic of the target structure responsive to the determined peaks.

Abstract: An optical wall-thickness measuring device for transparent articles. This invention may be practiced with any transparent material, amorphous or crystalline, which has two surfaces in close proximity to each other, and has flat or positively curved shape. As used herein, transparent means clear, translucent or partially transmitting such that a discernible image of the second surface reflection can be formed and detected at some wavelength of electromagnetic radiation.

Abstract: A method is provided for determining a thickness L of a chiral slab that refracts incident linearly polarized light into right (+) and left (?) circularly polarized beams. The method includes disposing the slab in an achiral medium, determining values of translation coefficients ?±, determining values for refraction angle differences (?+???), selecting pre- and post selection states |?i and |?j, projecting an emitted light beam through said achiral medium into the chiral slab a small established angle of incidence ?0, varying slab egress phase angles ?±, determining said pointer mean value x, calculating weak value Aw, and calculating the thickness as L = ? x ? Re ? ? A w . The achiral medium has an established index of refraction n0. The translation coefficients ?± establish refraction translation differences (?+???). The pre-selection state |?i establishes pre-selection alignment angle to satisfy ?=?/4.

Abstract: A system for inspecting specimens such as semiconductor wafers is provided. The system provides scanning of dual-sided specimens using a diffraction grating that widens and passes nth order (n>0) wave fronts to the specimen surface and a reflective surface for each channel of the light beam. Two channels and two reflective surfaces are preferably employed, and the wavefronts are combined using a second diffraction grating and passed to a camera system having a desired aspect ratio. The system preferably comprises a damping arrangement which filters unwanted acoustic and seismic vibration, including an optics arrangement which scans a first portion of the specimen and a translation or rotation arrangement for translating or rotating the specimen to a position where the optics arrangement can scan the remaining portion(s) of the specimen. The system further includes means for stitching scans together, providing for smaller and less expensive optical elements.

Abstract: Various embodiments are directed to systems and methods for measuring a thickness of a container. For example, a control device may receive data indicating a surface topology of the container and based on the surface topology of the container, instruct a multi-axis positioning system to position a sensor relative to a first point of the container such that: a distance from the sensor to a surface at the first point is about equal to a predetermined distance; and the sensor direction is about normal to the surface at the first point. Data indicating the thickness at the first point may be received from the sensor.

Abstract: A device for detecting the level of a liquid in a container, includes an optical structure facing at least partly the region inside the container in a position corresponding to a predefined level of the liquid and having a main surface, a first side surface and a second side surface which are inclined at about 45° with respect to the main surface and about 90° relative to each other; and an emitter and a receiver facing the main surface of the optical structure and able to send a radiation beam towards the first side surface and, respectively, receive a radiation beam emitted by the emitter and reflected by the first and second side surfaces, when the level of the liquid inside the container is lower than the predefined level. The structure extends mainly outside the container and faces the region inside the container only opposite the first side surface.

Abstract: A recording media deciding apparatus has: a light radiating portion which radiates light having a uniform light amount on a range corresponding to an image capturing range of a first surface of a bundle of recording media; a light detecting portion which captures an image of light emitted from a second surface different from the first surface of the bundle of the recording media; and a controller which decides on a type of the recording media based on an output of the light detecting portion.

Abstract: A method and system for real-time, in-line measurements of thicknesses of semiconductor layers of photovoltaic devices is provided. The method and system include taking ex-situ optical data measurements after deposition of the semiconductor layers. The measurements are then used to calculate the thicknesses of the layers in real-time using optical modeling software.

Abstract: A method and system for real-time, in-line calculations of opto-electronic properties and thickness of the layers of multi-layered transparent conductive oxide stacks of photovoltaic devices is provided. The method and system include taking measurements of each layer of the stack during deposition thereof. The measurements are then used to calculate the opto-electronic properties and thicknesses of the layers in real-time.

Abstract: A film thickness measuring device includes a spectroscopic sensor and a data processor, wherein the spectroscopic sensor measures spectroscopic data of a film coated on a substrate and the data processor obtains measured color characteristic variables from the measured spectroscopic data, compares the measured color characteristic variables with plural sets of theoretical color characteristic variables corresponding to plural sets of values, each set including one of plural values of thickness and one of plural values of index of refraction of the film, determines index of refraction of the film using the set of values corresponding to the set of theoretical color characteristic variables which minimizes a difference between the set of theoretical color characteristic variables and the measured color characteristic variables, and determines thickness of the film using the index of refraction of the film.

Abstract: An inspection process for detecting defects of thin type, on transparent containers for a series of inspection points distributed over an inspection region superposed according to a determined height of the container taken according to central axis thereof, and according to the circumference of the container comprising: sending a light beam so as to recover on a light sensor the reflected beams by the internal and external faces of the wall of the container, measuring at each inspection point the thickness of the wall as a function of separation at the level of the light sensor between the reflected beams by the internal and external faces, processing the thickness measurements by analysing their distribution over the inspection region to extract therefrom geometric characteristics, and comparing these geometric characteristics to reference values to determine if the container has a material distribution defect.

Abstract: A film thickness measuring device includes a spectroscopic sensor and a data processor, wherein the spectroscopic sensor measures spectroscopic data of a film coated on a substrate and the data processor obtains measured color characteristic variables from the measured spectroscopic data, compares the measured color characteristic variables with plural sets of theoretical color characteristic variables corresponding to plural sets of values, each set including one of plural values of thickness and one of plural values of index of refraction of the film, determines index of refraction of the film using the set of values corresponding to the set of theoretical color characteristic variables which minimizes a difference between the set of theoretical color characteristic variables and the measured color characteristic variables, and determines thickness of the film using the index of refraction of the film.

Abstract: An optical film thickness measuring device, enabling direct measurement of a film thickness of a product in real time accurately without a monitor substrate, includes: a projector, a light receiver, inner beam splitters disposed in a base substrate holder to reflect a measurement beam to a base substrate, an inner optical reflector that totally reflects a measurement beam from the closest inner beam splitter, external beam splitters the measurement beam from the inner beam splitters toward the light receiver, and an outer optical reflector that reflects the measurement beam from the optical reflector toward the light receiver. The measurement beam reflected by the inner beam splitters and the inner optical reflector is passed through the base substrate and then reflected by the external beam splitters and the outer optical reflector to be guided to the light receiver, so that the measurement beam is received by the light receiver.

Abstract: An apparatus arranged to analyze a multi-layer optical material structure, the apparatus constituted of: a control unit, a light source outputting light; and a light receiver arranged to receive the light from the light source after interaction with the target structure, the control unit arranged to: detect the amplitude of the received light as a function of wavelength; perform a transform of a function of the detected amplitudes to the optical thickness domain; determine, responsive to a planned composition of the target multi-layer structure, optical thickness and amplitude of expected peaks of the performed transform to the optical thickness domain which correspond with interactions with single interface between layers; identify actual peaks of the performed transform to the optical thickness domain which correspond with interfaces between layers; and determine at least one physical characteristic of the target structure responsive to the determined peaks.

Abstract: A method and test block for controlling weld penetration depth in a work piece are disclosed. The test block simulates a work piece relative to a welding process of the work piece. The test block includes a test welding path. The test welding path replicates a production welding path on a weld surface of the work piece. The test block includes a melt-thru surface that underlies the test welding path. The melt-thru surface is spaced apart from the test welding path by a spacing that decreases along a length of the test welding path. The spacing varies from more than a standard weld penetration depth to less than the standard weld penetration depth.

Abstract: One or more parameters of a sample that includes a textured substrate and one or more overlying films is determined using, e.g., an optical metrology device to direct light to be incident on the sample and detecting light after the incident light interacts with the sample. The acquired data is normalized using reference data that is produced using a textured reference sample. The normalized data is then fit to simulated data that is associated with a model having an untextured substrate and one or more variable parameters. The value(s) of the one or more variable parameters from the model associated with the simulated data having the best fit is reported as measurement result.

Abstract: The present invention is a film thickness measurement apparatus including a light source, a first optical path, a first condenser lens, a spectrometry unit, a second optical path, a second condenser lens, and a data processing unit. The light source emits measurement light having a predetermined wavelength range. The first optical path guides to an object to be measured the measurement light. The first condenser lens condenses the measurement light. The spectrometry unit obtains a wavelength distribution characteristic of reflectance or transmittance. The second optical path guides to the spectrometry unit the light reflected by or transmitted through the object. The second condenser lens condenses light at an end of the second optical path. The data processing unit analyzes the wavelength distribution characteristic obtained in the spectrometry unit to obtain a film thickness of the object.

Abstract: A method and means for determining the thickness, or curvature, of a thin film or stack of thin films disposed on the surface of a substrate having a curvature comprising generating a beam of radiation, focusing the beam through the one or more films onto a surface of the substrate, measuring the intensity across the reflected beam as a function of the angle of incidence of a plurality of rays derived from the focussed beam, determining the path of each of the plurality of rays and determining the thickness, or curvature of the film, or films, from the angular dependent intensity measurement.

Abstract: A method of controlling the polishing of a substrate includes polishing a substrate on a first platen using a first set of parameters, obtaining first and second sequences of measured spectra from first and second regions of the substrate with an in-situ optical monitoring system, generating first and second sequences of values from the first and second sequences of measured spectra, fitting first and second linear functions to the first and second sequences of values, determining a difference between the first linear function and the second linear function, adjusting at least one parameter of the first set of parameters based on the difference, and polishing the second substrate on the first platen using the adjusted parameter.

Abstract: There is provided a method of measuring a physical thickness of each of layers of a multilayer film, based on an optical thickness thereof. The method includes: (a) setting refractive indexes of the layers; (b) calculating a coefficient matrix using the refractive indexes; (c) providing light to the multilayer film so as to measure the optical thickness based on the light reflected by the multilayer film; and (d) calculating the physical thickness, based on the optical thickness and the coefficient matrix.

Abstract: The present invention provides apparatus for a non-contact method of obtaining accurate three-dimensional measurements of a dry contact lens, more specifically, using dry lens metrology to know the exact thickness of a contact lens.

Abstract: Methods and apparatuses for determining a thickness of a glass substrate are disclosed. The method includes conveying the glass substrate past an optical measurement head and determining a measurement separation distance dm between a first surface plane of the glass substrate and the optical measurement head. A position of the optical measurement head relative to the first surface plane of the glass substrate is adjusted based on the measurement separation distance dm between the first surface plane of the glass substrate and the optical measurement head such that the glass substrate is within a working range of the optical measurement head as the glass substrate is conveyed past the optical measurement head. A thickness Tm of the glass substrate is measured with the optical measurement head as the glass substrate is conveyed past the optical measurement head.

Abstract: Objects are to reduce the burden on an operator and to improve fabrication efficiency. A transparent conductive film or a transparent optical film formed on a substrate W is irradiated with line illumination light by means of a line illumination device 3, line reflected light reflected at the transparent conductive film or the transparent optical film is detected with a camera, a color evaluation value of the detected reflected light is measured, and a film thickness corresponding to the measured color evaluation value is obtained using a film-thickness characteristic in which the color evaluation value is associated with the film thickness.

Abstract: A method of inspecting a semiconductor substrate having a back surface and including at least one piece of metal embedded in the substrate comprises directing measuring light towards the back surface of the substrate and detecting a portion of the measuring light received back from the substrate. The method also includes determining a distance between the piece of metal and the back surface based upon the detected measuring light received back from the substrate.

Abstract: A method of measuring the extinction of light in a coating including the steps of: directing a light beam to a substrate to be coated at an angle of incidence for which the beam undergoes nominal total internal reflection; depositing a coating on the substrate such that the light beam will be waveguided in the coating thus reducing internal reflection for a period of deposition time; measuring a reduction of the internal reflection during deposition; and calculating an extinction value of the light beam in the deposited layer corresponding to the measured drop in internal reflection.

Abstract: Apparatus for performing Raman analysis may include a laser source module, a beam delivery and signal collection module, a spectrum analysis module, and a digital signal processing module. The laser source module delivers a laser beam to the beam delivery and signal collection module. The beam delivery and signal collection module delivers the laser source beam to a sample, collects Raman scattered light scattered from the sample, and delivers the collected Raman scattered light to the spectrum analysis module. The spectrum analysis module demultiplexes the Raman scattered light into discrete Raman bands of interest, detects the presence of signal energy in each of the Raman bands, and produces a digital signal that is representative of the signal energy present in each of the Raman bands. The digital signal processing module is adapted to perform a Raman analysis of the sample.

Abstract: The attenuation and other optical properties of a medium are exploited to measure a thickness of the medium between a sensor and a target surface. Disclosed herein are various mediums, arrangements of hardware, and processing techniques that can be used to capture these thickness measurements and obtain three-dimensional images of the target surface in a variety of imaging contexts. This includes general techniques for imaging interior/concave surfaces as well as exterior/convex surfaces, as well as specific adaptations of these techniques to imaging ear canals, human dentition, and so forth.

Abstract: The attenuation and other optical properties of a medium are exploited to measure a thickness of the medium between a sensor and a target surface. Disclosed herein are various mediums, arrangements of hardware, and processing techniques that can be used to capture these thickness measurements and obtain three-dimensional images of the target surface in a variety of imaging contexts. This includes general techniques for imaging interior/concave surfaces as well as exterior/convex surfaces, as well as specific adaptations of these techniques to imaging ear canals, human dentition, and so forth.