G01M11/00

PRECISION NON-CONTACT CORE IMAGING OF FIBER OPTIC ASSEMBLIES

A method, system, and computer program product for determining a core-to-ferrule offset of a ferrule for a fiber optic connector. A reference ferrule is physically aligned with a core imager by positioning the reference ferrule so that edges of the reference ferrule in a plurality of profile images are aligned with fiducial markers in the images. The reference ferrule is incrementally rotated about its longitudinal center access, a core image captured at each rotational angle, and a reference core-to-ferrule offset determined based on the core images. A test ferrule is physically aligned with the core imager by positioning the test ferrule so that edges of the test ferule are aligned with the edges of the reference ferrule in a plurality of profile images. The core-to-ferrule offset of the test ferrule is then determined based on an offset between the test and reference cores in a composite core image.

Sensor calibration

A method includes providing a fixture including a target in a field of view of a sensor mounted to a vehicle. The target is detectable by the sensor. The fixture includes a first rangefinding device and a second rangefinding device spaced from the first rangefinding device. The method includes measuring a first angle and first distance from the first rangefinding device to a first known point on the vehicle; measuring a second angle and second distance from the second rangefinding device to a second known point on the vehicle; determining a position and orientation of the target in a coordinate system relative to the vehicle based on the first angle, the first distance, the second angle, and the second distance; and calibrating the sensor based on the position and orientation of the target.

MEDICAL LIGHTING DEVICE
20220364952 · 2022-11-17 · ·

A medical lighting device according to the present invention includes a light source unit that emits light, an optical fiber that guides and emits the light having emitted from the light source unit and having entered inside the optical fiber, first and second detection units that are provided in the vicinity of an emission end including an emission end for the light of the optical fiber and detect the light in the optical fiber, and a control unit that determines, based on detection values of the light detected by the first and second detection units, normality/abnormality in the detection values of the respective detection units and outputs determined results.

A METHOD TO DETERMINE LINE ANGEL AND ROTATION OF MULTPLE PATTERNING
20220364951 · 2022-11-17 ·

A method and apparatus for determining a line angle and a line angle rotation of a grating or line feature is disclosed. An aspect of the present disclosure involves, measuring coordinate points of a first line feature using a measurement tool, determining a first slope of the first line feature from the coordinate points, and determining a first line angle from the slope of the first line feature. This process can be repeated to find a second slope of a second line feature that is adjacent to the first line feature. The slope of the first and second line features can be compared to find a line angle rotation. The line angle rotation is compared to a design specification and a stitch quality is determined.

Fabrication method for endcapped fiber laser pigtails with sub-micron virtual waist positional accuracy

Arrays of fiber pigtails can be used to project and receive light. Unfortunately, most fiber pigtail arrays are not aligned well enough for coherently combining different optical beams. This imprecision stems in part from misalignment between the optical fiber and the endcap spliced to the end of the optical fiber. The endcap is often polished, curved, or patterned, causing the light emitted by the endcapped fiber to refract or diffract as it exits the endcap. This refraction or diffraction shifts the apparent position of the beam waist from its actual position. Measuring this virtual beam waist position before and after splicing the endcap to the fiber increases the absolute precision with which the fiber is aligned to the endcap. This increase in absolute precision reduces the deviation in virtual beam waist position among endcapped fibers, making it easier to produce arrays of endcapped fibers aligned precisely enough for coherent beam combining.

REAL-EQUIVALENT-TIME OSCILLOSCOPE WITH TIME DOMAIN REFLECTOMETER
20220357237 · 2022-11-10 · ·

A test and measurement device includes one or more ports configured to connect to a device under test (DUT), a time domain reflectometry (TDR) source configured receive a source control signal and to produce an incident signal to be applied to the DUT, one or more analog-to-digital converters (ADC) configured to receive a sample clock and sample the incident signal from the TDR source and a time domain reflection (TDR) signal or a time domain transmission (TDT) signal from the DUT to produce an incident waveform and a TDR/TDT waveform, one or more processors configured to execute code to cause the one or more processors to: control a clock synthesizer to produce the sample clock and the source control signal, and use a period of the TDR source, a period of the sample clock, and the number of samples to determine time locations for samples in the incident waveform and the TDR/TDT waveform, and a display configured to display the incident waveform and the TDR/TDT waveform. A method of sampling a waveform using a real-equivalent-time oscilloscope having a time domain reflectometry source, comprising: controlling a clock synthesizer to produce a sample clock and a source control signal; using a time domain reflectometry (TDR) source to receive the source control signal and to produce an incident signal to be applied to a device under test (DUT); receiving the sample clock at one or more analog-to-digital converters (ADC) and sampling the incident signal from the TDR source and a TDR/TDT signal from the DUT to produce an incident waveform and a TDR/TDT waveform; determining time locations for samples in the incident waveform and the TDR/TDT waveform, using a period of the TDR source, a period of the sample clock, and a number of samples; and displaying the incident waveform and the TDR/TDT waveform.

Method and System for Simulating Propagation of a Composite Electromagnetic Beam

A system for simulation of a composite beam is disclosed. The system can comprise a memory storing executable instructions and one or more processors coupled to the memory to execute the executable instructions. The one or more processors can be configured to generate a representation of the original beam pattern transmitted via a propagation of the composite beam, to invoke a propagation model that represents a distortion for the propagation of the composite beam, and to determine a representation of a distorted beam pattern based on the propagation model and on the representation of the original beam pattern transmitted via the propagation.

Optical time domain reflectometer (OTDR)-based classification for fiber optic cables using machine learning
11573152 · 2023-02-07 · ·

In one embodiment, a device receives optical time domain reflectometer (OTDR) trace samples, each sample labeled with an associated fiber optic cable condition. The device alters the received OTDR trace samples to generate a set of synthetic OTDR trace samples. Each synthetic sample is labeled with the label of the received sample that was altered to generate the synthetic sample. The device trains a machine learning-based classifier using a training dataset that comprises the synthetic OTDR trace samples. The device uses the trained classifier to identify a condition along a particular fiber optic cable based on OTDR trace data obtained from that cable.

MULTIMODE OPTICAL FIBER CORE CANE CLASSIFICATION METHOD

Methods for classifying a core cane of an multimode optical fiber are disclosed. In embodiments, the method includes determining a relative refractive index profile Δ(r) of the core cane; fitting the relative refractive index profile Δ(r) to an alpha profile Δ.sub.fit(r) defined by:

[00001] Δ fit ( r ) = Δ o , fit ( 1 - ( r a fit ) α fit )

where Δ.sub.o,fit is a relative refractive index at a longitudinal centerline of the core cane, α.sub.fit is a core shape parameter, and a.sub.fit is an outer radius of the core cane; generating a non-alpha residual profile Δ.sub.diff(r)=Δ(r)−Δ.sub.fit(r) for the core cane; computing one or more metrics from Δ.sub.diff(r), and using the one or metrics in a classification of the core cane, the classification comprising a prediction of whether a bandwidth at a pre-determined wavelength of an optical fiber drawn from a preform comprising the core cane exceeds a pre-determined bandwidth at the pre-determined wavelength.

Signal Detection Method and Optical Time-Domain Reflectometer
20230031468 · 2023-02-02 ·

An optical time-domain reflectometer (OTDR), where a laser emitting apparatus of the OTDR outputs a first optical signal in a first time period. A signal modulation apparatus of the OTDR generates a pulse signal based on the first optical signal, and outputs the pulse signal to an optical fiber in a second time period, where the first time period includes the second time period. A receiver of the OTDR receives a scattered signal from the optical fiber, where a frequency of the scattered signal is the same as a frequency of the first optical signal. Then, the laser emitting apparatus outputs a second optical signal in a third time period, where a frequency of the second optical signal is different from the frequency of the first optical signal. The second optical signal is used as a local oscillator signal to implement coherent detection in the receiver.