Abstract: The present invention predicts prior to a laser iris color-change procedure what a patient's iris color will be after the procedure. The present invention does so by identifying and measuring a variety of anatomical features of the patient's eye that affect or are otherwise relevant to predicting the patient's post-operative iris color, translating these measurements into a post-operative iris color prediction, and communicating this prediction to the patient in a manner sufficient to manage the patient's expectations with respect to the aesthetic outcome of the procedure.

Abstract: An optical coherence tomography (OCT) system comprises: an imaging catheter; a calibration phantom removably arranged at least partially surrounding the distal end of the catheter; and a processor configured to control the catheter to acquire OCT images. The phantom has known dimensions and specific optical properties which provide non-changing calibration fiducials that span the imaging range of the system. The phantom is imaged by the catheter upon first connection to the system. The processor calculates a thickness of the phantom in the OCT image, and preforms z-offset calibration by setting the position of a phantom surface in the OCT image to a known nominal value. The known nominal value is related to one or more of the known thickness of the phantom or a diameter of the catheter sheath or a nominal angle of the light beam or the imaging range of the system.

Abstract: An aspect provides an image processing apparatus processing three-dimensional image data generated based on a photoacoustic wave generated from inside of a subject.

Abstract: According to one aspect, the invention relates to a system (101) for in vivo, full-field interference microscopy imaging of a scattering three-dimensional sample.

Abstract: An optical coherence tomography instrument suitable for imaging a retina is disclosed. In the instrument, an adjustable optical frequency shifter, which can be or include an acousto-optic modulator or electro-optic modulator, is arranged either (i) between a coupler and a reference optical system, (ii) in a reference optical system, (iii) between the coupler and a front-end optical system, or (iv) in a front-end optical system. The optical frequency of reference light or signal light may adjustably be increased or decreased. In operation, a subject is arranged such that its retina is in the focal depth of the front-end optical system. The increase or decrease in the optical frequency of the reference light or the sample light can be adjusted. Thereby, an interferogram representing a depth structure at the retina obtained between returning signal light and returning reference light may be brought to lie within a detection bandwidth of the instrument.

Abstract: Examples of the disclosure relate to an apparatus, an optical coherence tomography device, a wearable electronic device and method of forming an apparatus for optical coherence tomography. The apparatus comprises at least one layer of silicon dioxide and an integrated optoelectronic circuit. The integrated optoelectronic circuit comprises at least an interferometer configured for optical coherence tomography wherein the integrated optoelectronic circuit is formed within the at least one layer of silicon dioxide.

Abstract: A system for imaging a body lumen includes a controller and a display. The controller is configured to connect to a proximal end of a catheter having an optical fiber extending along the length of an elongate catheter body. The controller is further configured to rotate a distal end of the optical fiber from a location near a proximal end of the elongate catheter body, acquire optical coherence tomography (OCT) images using the optical fiber as the distal end of the optical fiber rotates, and determine a rotational lag of the distal end of the optical fiber. The display is configured to display one or more OCT images corrected for the rotational lag.

Abstract: Provided is a holographic microscope including an input optical system configured to emit polarized input beam, a first beam splitter configured to emit an object beam by reflecting a portion of the polarized input beam, and emit a reference beam by transmitting a remaining portion of the polarized input beam, a reference optical system configured to separate the reference beam into a first reference beam and a second reference beam, a camera configured to receive the first reference beam and the second reference beam and the object beam that is reflected by an inspection object, the camera including a micro polarizer array, wherein a first polarization axis of the first reference beam is perpendicular to a second polarization axis of the second reference beam.

Abstract: Systems and methods for image-based guidance using automated instrument tracking. An en face image frame, generated from en face image data captured by a first imaging system (e.g., an SER imaging system), is analyzed to determine a location of an instrument in the first imaging plane. A control signal is then generated for the movement stage to control the scanning movement of a depth-based imaging system (e.g., an OCT imaging system) based on the determined location of the instrument. In some implementations, a trained neural-network is used to determine the location of the instrument based on the en face image frame and, in some implementations, the control signal adjusts the speed of the scanning movement to capture image data at a higher density7 at areas corresponding to the determined location of the instrument.

Abstract: A multi-modal functional OCT imaging methodology and system are provided that enable concurrent intrinsic optical signal (IOS) imaging of stimulus-evoked neural activity and hemodynamic responses at capillary resolution. An OCT angiography (OCTA)-guided IOS analysis is used to separate neural-IOS and hemodynamic-IOS changes in the same retinal image sequence. The OCTA-guided IOS data processing used for this purpose differentiates two functional images, namely, a neural-IOS map and a hemodynamic-IOS map, from the same image dataset.

Abstract: Exemplary apparatus can be provided which can include a laser arrangement that is configured to provide a laser radiation, and including an optical cavity. The optical cavity can include a dispersive optical waveguide first arrangement having first and second sides, and which is configured to (i) receive at least one first electro-magnetic radiation at the first side so as to provide at least one second electro-magnetic radiation, and (ii) to receive at least one third electro-magnetic radiation at the second side so as to provide at least one fourth electro-magnetic radiation. The first and second sides are different from one another, and the second and third radiations are related to one another. The optical cavity can also include an active optical modulator second arrangement which can be configured to receive and modulate the fourth radiation so as to provide the first electro-magnetic radiation to the first arrangement.

Abstract: An ophthalmologic information processing apparatus according to the embodiments include a generator, an extractor, and a phase correction unit. The generator is configured to generate a phase difference profile by performing averaging processing in a depth direction on phase differences obtained by calculating for each depth position of A-lines between two adjacent B-frames of complex OCT data of a subject's eye. The extractor is configured to a phase drift from the phase difference profile generated by the generator. The phase correction unit is configured to correct a phase of first complex OCT data of any one of the two B-frames based on the phase drift extracted by the extractor.

Abstract: Systems and methods for assessing glaucoma loss using optical coherence topography. One method according to an aspect comprises receiving optical coherence image data and assessing functional glaucoma damage from retinal optical coherence image data. In an aspect, the systems and methods can map regions and layers of the eye to determine structural characteristics to compare to functional characteristics.

Abstract: An optical system comprises a first optical path configured to supply a first light with a first range of wavelengths; a second optical path configured to supply a second light with a second range of wavelengths shorter than the first range of wavelengths; a third optical path configured to supply a third light with a third range of wavelengths shorter than the second range of wavelengths; an optical I/O unit configured to emit the first light, the second light and the third light to a target and acquire a light from the target; a reference unit configured to split off a reference light from the third light; and a detector that includes a range of detection wavelengths shared with a CARS light and an interference light.

Abstract: Disclosed are methods and systems correcting bulk-motion artifacts in phase-based functional OCT images. The disclosed methods and systems are based on the use of the standard deviation of the phase shift signal present in phase-based OCT imaging. When applied with functional OCT techniques such as OCT angiography, Doppler OCT, and OCT elastography, the disclosed methods provide improved image quality and decreased computational cost compared to other methods of bulk motion compensation.

Abstract: The present disclosure relates to a system for sensing temperature changes on a microsecond scale. The system uses a multi-channel pyrometer that works in the NIR spectrum to receive thermal radiation. Each channel includes an interference filter tuned to pass thermal radiation within a specified wavelength range, and a detector. Each detector detects thermal radiation focused on it. Each channel further includes an interference filter which reflects thermal radiation which does not pass through it to a subsequent downstream interference filter of a subsequent channel. Each subsequent interference filter is oriented to reflect the thermal radiation not passing through it to a next downstream one of the subsequent interference filters. A subsystem is included for receiving the output from the detectors and determining sensed temperature data therefrom, allowing measurement of temperatures down to 800 K.

Abstract: One or more devices, systems, methods, and storage mediums for detecting and guiding optical connection(s) using one or more imaging modalities are provided herein. Examples of applications include imaging, evaluating and diagnosing biological objects, such as, but not limited to, for Gastro-intestinal, cardio and/or ophthalmic applications, and being obtained via one or more optical instruments, such as, but not limited to, optical probes, catheters, capsules and needles (e.g., a biopsy needle). Devices, systems, methods, and storage mediums may include or involve a method, such as, but not limited to, for guiding and/or determining status of engagement and/or disengagement of one or more optical connections. A device, system, method, or storage medium may detect, monitor, and/or guide a probe/catheter to minimize, reduce, and/or avoid engagement and disengagement failures and to have a robust means of determining status of probe/catheter engagement to an apparatus or system.

Abstract: A non-contact tool measurement apparatus is used in a machine tool environment. The apparatus includes a transmitter including a first aperture and a laser for generating light that is emitted from the transmitter through the first aperture towards a tool-sensing region. A receiver includes an optical detector and is arranged to receive light from the tool-sensing region. A processor analyses the light detected by the optical detector to enable the measurement of tools in the tool-sensing region. The laser is capable of generating light having a wavelength of less than 590 nm thereby enabling the size of the first aperture to be reduced resulting in a reduction in contaminant ingress. In one embodiment, the laser generates blue light.

Abstract: An optical coherence tomography apparatus includes a branching and merging device that branches a light beam emitted from a wavelength sweeping laser light source into an object light beam and a reference light beam, a balanced photodetector that generates information about a change in an intensity ratio of interference light beams, which are generated by the interference between the object light beam and the reference light beam, wherein the object light beam is scattered from the measurement object after being transmitted through the transparent substrate including a structure that changes a thickness, and a control unit that acquires structural data of the measurement object in a depth direction based on the information about the change in the intensity ratio of the interference light beams and connects the structural data while moving an irradiation position of the object light beam with a position of the above structure as a reference.

Abstract: Aspects of the disclosure relate to systems, methods, and algorithms to perform wavenumber linearization and dispersion correction in optical systems without the need for hardware modifications, empirical adjustments, precise mirror alignment, and which can be conducted at low computational costs and in real-time. A one-time calibration process can generate spectra or calibration criteria, including wavenumber-linearization criteria, dispersion correction, and spectral flattening spectra, which can be used to correct an optical coherence tomogram in real time.

Abstract: In part, the disclosure relates to determining a stent deployment location and other parameters using blood vessel data. Stent deployment can be planned such that the amount of blood flow restored from stenting relative to an unstented vessel increases one or more metrics. An end user can specify one or more stent lengths, including a range of stent lengths. In turn, diagnostic tools can generate candidate virtual stents having lengths within the specified range suitable for placement relative to a vessel representation. Blood vessel distance values such as blood vessel diameter, radius, area values, chord values, or other cross-sectional, etc. its length are used to identify stent landing zones. These tools can use or supplement angiography data and/or be co-registered therewith. Optical imaging, ultrasound, angiography or other imaging modalities are used to generate the blood vessel data.

Abstract: The invention describes a metrology system allowing for the reduction of the errors caused by vibration of the production floor and allowing for measurements of the thickness of wafers in motion. This is accomplished by performing simultaneous measurements of spectra containing interference signals containing distance information using a plurality of probes positioned on both sides of the measured wafer on the same detector at the same time or by means of plurality of synchronized detectors. System is also able to measure thickness of the individual optically accessible layers present in the sample.

Abstract: An OCT apparatus of an exemplary aspect includes an OCT scanner, image data generating unit, registration unit, and image data composing unit. The OCT scanner is configured to acquire three dimensional data sets by applying an OCT scan to mutually different three dimensional regions of a sample. The image data generating unit is configured to generate a plurality of pieces of image data from the three dimensional data sets. The registration unit is configured to perform a first registration between the plurality of pieces of image data by applying an image correlation calculation to each of overlap regions in the plurality of pieces of image data. The image data composing unit is configured to compose the plurality of pieces of image data based on a result of the first registration.

Abstract: Disclosed is an OCT system, in particular a mid-IR OCT system, comprising: an upconversion module configured to frequency upconvert light received or receivable by the upconversion module and which is in a wavelength range between a first wavelength and a higher second wavelength, the difference between the second wavelength and the first wavelength being at least 300 nm or larger, and the wavelength range having a center wavelength at 2.8 ?m or larger, the center wavelength being defined by the average value between the first wavelength and the second wavelength.

Abstract: A system including one or more waveguides to receive a first returned reflection having a first lag angle and generate a first waveguide signal, receive a second returned reflection having a second lag angle different from the first lag angle, and generate a second waveguide signal. The system includes one or more photodetectors to generate a first output signal within a first frequency range, and generate, based on the second waveguide signal and a second LO signal, a second output signal within a second frequency range. The system includes an optical frequency shifter (OFS) to shift a frequency of the second LO signal to cause the second output signal to shift from within the second frequency range to within the first frequency range to generate a shifted signal. The system includes a processor to receive the shifted signal to produce one or more points in a point set.

Abstract: A light detection device includes: a first support part disposed on a mounting surface of the wiring board; a Fabry-Perot interference filter disposed in a first support region of the first support part; and a temperature detector, wherein the temperature detector is disposed on the mounting surface such that at least a part of the temperature detector overlaps a part of the Fabry-Perot interference filter when seen in a first direction perpendicular to the mounting surface and such that at least a part of the temperature detector overlaps a part of the first support part when seen in a second direction in which the first support part and the light detector are aligned with each other, and wherein a first distance between the temperature detector and the first support part in the second direction is smaller than a first width of the first support region in the second direction.

Abstract: Provided are systems and methods that allow for brightfield imaging in a flow cytometer, allowing for collection of fluorescence and high-quality image date. The disclosed technology also gives rise to an illumination pattern that allows a user to create different oblique or structured illumination profiles within a static system. With the disclosed approach, a user can illuminate a sample from a first direction (e.g., with laser illumination configured to give rise to one or more of fluorescence information and scattering information), collect scattering information from a second direction, collect fluorescence information from a third direction, and capture an image of the sample from a fourth direction. (Two or more of the foregoing can be accomplished simultaneously.) Also as described elsewhere herein, an illumination used to illuminate the sample for visual image capture can be communicated to the same through a lens that also collects fluorescence from the sample.

Abstract: Arrangement for acquiring images for producing a head related transfer function filter is disclosed. In the arrangement the camera of a mobile phone or similar portable device is adjusted for the imaging. All acquired images are analyzed and only suitable images are sent further for producing the head related transfer filter. The arrangement is further configured to provide instructions to the user so that the whole head and other relevant body parts are sufficiently covered.

Abstract: The invention relates to a method for determining a position of an object, which comprises at least one non-linear component, in particular one semiconductor component, which, when irradiated with high-frequency transmitted signals from at least two different positions, produces and emits object signals having twice and/or three times the frequency of the respective transmitted signals.

Abstract: A light detection and ranging (LIDAR) transceiver includes optical antenna arrays and an optical switch. Some of the optical antenna arrays include a number of optical antennas and an optical splitter coupled to the optical antennas. The optical splitter may include a number of passive optical splitters. The optical splitter provides a portion of an input signal to the optical antennas. The optical switch is configured to selectively provide the input signal to at least one of the plurality of optical antenna arrays. The optical switch enables addressable field of view scanning by selectively providing the input signal to the plurality of antenna arrays, one array at a time.

Abstract: The present disclosure relates to devices, systems and methods for extracting physiological information indicative of at least one vital sign of a subject. An embodiment of a device comprises a pre-treatment unit configured to derive at least three detection signals from electromagnetic radiation reflected from a skin region of a subject, wherein at least two detection signals comprise wavelength-dependent reflection information in a different wavelength channel and at least two detection signals comprise reflection information in different polarization channels having different polarization directions.

Abstract: In some embodiments, systems, methods, and media for multiple reference arm spectral domain optical coherence tomography are provided which, in some embodiments, includes: a sample arm coupled to a light source; a first reference arm having a first path length; a second reference arm having a longer second path length; a first optical coupler that combines light from the sample arm and the first reference arm; a second coupler that combines light from the sample arm and the second reference arm; and an optical switch comprising: a first input port coupled to the first optical coupler; a second input coupled to the second coupler via an optical waveguide that induces a delay at least equal to an acquisition time of an image sensor; and an output coupled to the image sensor.

Abstract: A gaming machine includes at least one image sensor for capturing an image including a player area associated with the gaming machine and logic circuitry in communication with the image sensor. The logic circuitry establishes a facial image mask defining an area of interest within the player area, receives the captured image from the image sensor, applies the facial image mask to the captured image to extract player image data from the captured image data, detects any faces within the player image data, compares, in response to detecting a face of a player within the player image data, the detected face with a player database to identify a player account associated with the player, and links, in response to identifying a matching player account based on the comparison, the matching player account to activities of the player at the gaming machine.

Abstract: An ophthalmic device includes a two-dimensional image acquisition unit that acquires a two-dimensional image by photographing the front of an eye to be examined with a color camera; a three-dimensional image acquisition unit that acquires a three-dimensional image of the eye to be examined by optical coherence tomography; and a correspondence definition data generation unit that generates correspondence definition data in which the position of a predetermined site of the eye to be examined in the three-dimensional image when the predetermined site is photographed as the three-dimensional image is associated with the position of the predetermined site in the two-dimensional image when the predetermined site is photographed as the two-dimensional image.

Abstract: An architecture for a chip-scale optical phased array-based scanning frequency-modulated continuous wave (FMCW) Light-detection and ranging (LiDAR) device is described. The LiDAR device includes a laser, a transmit optical splitter, an optical circulator, photodetectors, and an optical phased array. The laser, the transmit optical splitter, the optical circulator, the photodetectors, and the optical phased array are arranged as a chip-scale package on a single semiconductor substrate. The laser generates a first light beam that is transmitted to the optical phased array aperture via the transmit optical splitter, the optical circulator, and the optical phased array. A fraction of the first light beam is transmitted to the photodetectors via the transmit optical splitter to serve as the optical local oscillator (LO), the aperture of the optical phased array captures a second light beam that is transmitted to the photodetectors via the optical phased array and the optical circulator.

Abstract: An ophthalmic device includes a two-dimensional image acquisition unit that acquires a two-dimensional image by photographing the front of an eye to be examined with a color camera; a three-dimensional image acquisition unit that acquires a three-dimensional image of the eye to be examined by optical coherence tomography; and a correspondence definition data generation unit that generates correspondence definition data in which the position of a predetermined site of the eye to be examined in the three-dimensional image when the predetermined site is photographed as the three-dimensional image is associated with the position of the predetermined site in the two-dimensional image when the predetermined site is photographed as the two-dimensional image.

Abstract: A vacuum device comprises a vacuum generator and a vacuum interface for fluidically coupling the vacuum generator to a vacuum cavity for affixing an ophthalmological patient interface on a patient's eye. The vacuum device comprises a movement detector which is configured to detect movements of the patient's eye and a control unit that is configured to detect a faulty fluidic coupling of the vacuum cavity on the basis of a pressure that is ascertained by a coupled pressure sensor and to produce a control signal for interrupting an ophthalmological treatment that is carried out by an ophthalmological treatment device if an eye movement is detected by the movement detector at the same time as the detected faulty fluidic coupling of the vacuum cavity.

Abstract: An OCT apparatus and method for characterization of a fluid adjacent to a tympanic membrane has a low coherence source which is coupled to a splitter which has a measurement path and a reference path. The reference path is temporally modulated for length, and the combined signals from the reference path and the measurement path are applied to a detector. The detector examines the width of the response and the time variation when an optional excitation source is applied to the tympanic membrane, the width of the response and the time variation forming a metric indicating the viscosity of a fluid adjacent to the tympanic membrane being measured.

Abstract: An optical coherence tomography (OCT) engine includes a digital Fourier-Transform (dFT) spectrometer, a tunable delay line, and a high-speed optical phased array (OPA) scanner integrated onto a single chip. The broadband dFT spectrometer offers superior signal-to-noise ratio (SNR) and fine axial resolution; the tunable delay line ensures large imaging depth by circumventing sensitivity roll-off; and the OPA can scan the beams at GHz rates without moving parts. Unlike conventional spectrometers, the dFT spectrometer employs an optical switch network to retrieve spectral information in an exponentially scaling fashion—its performance doubles with every new optical switch added to the network. Moreover, it also benefits from the Fellgett's advantage, which provide a significant SNR edge over conventional spectrometers. The tunable delay line balances the path length difference between the reference and sample arms, avoiding any need to sample high-frequency spectral fringes.

Abstract: A method for monitoring a property of nanoparticles in a flowing suspension comprises providing a sample comprising a flowing suspension. The method further comprises non-invasively monitoring a size distribution of nanoparticles of the flowing suspension using Fourier domain low-coherence interferometry, FDLCI, wherein the monitoring comprises deriving a time and optical path length resolved LCI light scattering signal l(t,z) from time resolved LCI wavelength spectra of interference and deriving information indicative of the size of the particles in the sample based on said time and optical path length resolved LCI light scattering signal using optical path length resolved temporal autocorrelation functions or optical path length resolved frequency power spectra of the spatiotemporal FDLCI signal.

Abstract: Disclosed is an optical coherence tomography (OCT) system according to an exemplary embodiment of the present disclosure.

Abstract: A method for mitigating modal noise includes applying a time-varying mechanical force to a fiber segment of the multimode optical fiber in at least a first direction orthogonal to a fiber axis of the multimode optical fiber within the fiber segment. A modal-noise mitigator for a multimode optical fiber includes an actuator configured to apply a time-varying mechanical force to a fiber segment of the multimode optical fiber in at least a first direction orthogonal to a fiber axis of the multimode optical fiber within the fiber segment.

Abstract: Disclosed herein is a method for depth-profiling of samples including a target region including a lateral structural feature. The method includes obtaining measured signals of the sample and analyzing thereof to obtain a depth-dependence of at least one parameter characterizing the lateral structural feature. The measured signals are obtained by repeatedly: projecting a pump pulse on the sample, thereby producing an acoustic pulse propagating within the target region; Brillouin-scattering a probe pulse off the acoustic pulse within the target region; and detecting a scattered component of the probe pulse to obtain a measured signal. In each repetition the respective probe pulse is scattered off the acoustic pulse at a respective depth within the target region, thereby probing the target region at a plurality of depths. A wavelength of the pump pulse is at least about two times greater than a lateral extent of the lateral structural feature.

Abstract: An exemplary system for generating an image(s) of a sample(s) can include, for example, an imaging arrangement that can include a superluminescent diode (SLD) configured to generate a radiation(s) to be provided to the sample(s), and a spectrometer configured to (i) sample an A-line sampling rate of at least about 200 kHz, (ii) receive a resultant radiation from the sample(s) based on the sampling rate, and (iii) generate information based on the resultant radiation, and a computer hardware arrangement configured to generate the image(s) of the sample(s) based on the information received from the spectrometer. The imaging arrangement can be an interferometric imaging arrangement, which can be an optical coherence tomography imaging (OCT) arrangement. The computer hardware arrangement can be further configured to facilitate a plurality of b-scan acquisitions of the sample(s) and facilitate the b-scan acquisitions in order to generate the image(s).

Abstract: There is provided an image processing device for observing an inside of an eye in a wider range. The image processing device includes an integration processing unit that integrates ophthalmologic images acquired by a plurality of types of ophthalmologic image capturing devices by correlating intraocular positions and generates one integrated image indicating intraocular information in a range wider than a range indicated by each of the ophthalmologic images.

Abstract: An OCT axial length measurement device is configured to measure an area of the retina within a range from about 0.05 mm to about 2.0 mm. The area can be measured with a scanned measurement beam or plurality of substantially fixed measurement beams. The OCT measurement device may comprise a plurality of reference optical path lengths, in which a first optical path length corresponds to a first position of a cornea, and a second optical path length corresponds to a second position of the retina, in which the axial length is determined based on a difference between the first position and the second position. An axial length map can be generated to determine alignment of the eye with the measurement device and improve accuracy and repeatability of the measurements. In some embodiments, the OCT measurement device comprises a swept source vertical cavity surface emitting laser (“VCSEL”).

Abstract: An optical coherence tomography (OCT) system (63) is used to inspect bonding points (66A, 66B, 66C) sandwiched between two materials (layers 62, 64 of e.g. displays). The OCT differentiates between a bonding point, e.g. a weld, and air gaps between the two materials. The bonding points are identified as breaks in the air gap between the materials. By extracting various physical characteristics of the bonding points and the gap between the two materials, the present system determines whether the bonding is faulty.

Abstract: A photonic circulator deployed on a chip-scale light-detection and ranging (LiDAR) device includes a first arm that includes a first waveguide that is bonded onto a first member at a first bonding region, and a second arm that includes a second waveguide that is bonded onto a second member at a second bonding region. A first thermo-optic phase shifter is arranged on the first member and collocated with the first waveguide, and a second thermo-optic phase shifter is arranged on the second member and collocated with the second waveguide. The magneto-optic material and the first thermo-optic phase shifter of the first member cause a first phase shift in a first light beam travelling through the first waveguide, and the magneto-optic material and the second thermo-optic phase shifter of the second member cause a second phase shift in a second light beam travelling through the second waveguide.

Abstract: A method of measuring working distance between a handheld digital device and eyes of a user, including capturing an image of at least eyes of a user via an onboard camera of the handheld digital device while the user is viewing a display of the handheld digital device and comparing an apparent angular size of a structure of the eyes or face of the user to a previously captured image of the structure of the eyes or the face that was taken in the presence of an object of known size. The method further includes calculating a working distance based on the apparent angular size of the structure of the eyes or the face; and saving at least the working distance to memory or reporting out the calculated working distance on the display. A handheld digital device programmed with an algorithm to perform the method is also included.

Abstract: A signal control module integrated to a low coherence interferometry including a one-dimensional (1D) array image sensor is provided. The signal control module includes an image acquisition controller and a signal controller. The image acquisition controller sends a 1D image acquisition control signal. The signal controller sends a two-dimensional (2D) image acquisition control signal, wherein the 1D and 2D image acquisition control signals are synchronized with each other. The 1D array image sensor captures 1D image information of an object-to-be-tested at different positions along a direction according to the 1D and 2D image acquisition control signals. The 1D image information constitutes 2D image information. Furthermore, a low coherence interferometry is provided.