Aspects of the disclosure provide for automated self-inspection by an OCT imaging engine or device, to identify and resolve failures or inefficiencies in the hardware and/or software of the system or device during imaging. An OCT imaging engine can include a catheter connection check system for checking the quality of a physical connection point between a catheter and other components of an OCT imaging device or system. In some examples, the OCT imaging engine includes a self-inspection engine implemented to perform routine self-inspection by using a reference reflector internal to the OCT imaging engine to generate system performance data. The OCT imaging engine can use the system performance data to periodically search for and resolve failures or inefficiencies in the system. The OCT imaging engine can perform a self-calibration process to perform k-linearization and/or correct for chromatic dispersion using mirror measurements collected from an internal reference reflector.

An integrated circuit that includes a wavelength meter is described. This integrated circuit may include: a set of interferometers having integer multiples of a phase or a delay, where the set of interferometers provide outputs corresponding to a range from an MSB to an LSB of a wavelength in an optical signal. For example, the set of interferometers may include MZIs or ring resonators. Moreover, the integrated circuit may include a converter that provides digital electrical signals that specify the range from the MSB to the LSB. Note that the set of interferometers may have different FSRs, where an interferometer that provides an output corresponding to the MSB has a largest FSR and a smallest phase or delay, and a second interferometer that provides a second output corresponding to the LSB has a smallest FSR and a largest phase or delay.

A method of determining a bonding energy of a bonded wafer includes receiving the bonded wafer including a first wafer bonded with a second wafer, and inserting a blade between the first wafer and the second wafer to form a crack between the first wafer and the second wafer, the crack extending from a portion of the blade contacting the first wafer and the second wafer to a point where the first wafer and the second wafer are still bonded. The method further includes passing light beams through the crack at an outer edge of the bonded wafer, and collecting light beams transmitting through the crack at a light detector. And the method further includes determining the bonding energy of the bonded wafer based on a light intensity of the collected light beams.

An operation method of an image capture device includes steps as follows. The MEMS driver is controlled through the field programmable gate array (FPGA) independently to adjust at least one micro electro mechanical system (MEMS) scanning mirror of the optical system; at least one digital signal provided by the linear image sensor module is processed through the FPGA directly so as to obtain at least one image data.

The present invention relates to an objective (3) for a confocal system (1) of spectral interferometric measurement, comprising: a source hole (14); a second beam splitter (12) having a partially reflective face (12a), a first beam splitter (10) having a face which is configured to form a reference surface (6) and being located between the source hole (14) and the second beam splitter (12); andlenses (11, 13). The first and second beam splitters are positioned in the objective (3) such that an optical distance (d.sub.ref) between the reference surface (6) and the partially reflective surface (12a) is substantially equal to an optical distance (d.sub.m) between the partially reflective surface (12a) and a focal plane of the objective (3).

Systems and methods are provided for a digital holography system. The subject system uses wide-bandwidth data, monitor beams, and signal beams to form a digital interference, yielding a reference phase and angle that can be used to compensate DH phase errors. DH systems disclosed herein can provide an ability to sense and correct for phase errors and/or instabilities to perform DH vibrometry. Such a system provides a compact and low-cost solution to improve sensing in, for example, systems that rely on phase stability for precision 3D and/or vibration imaging.

Systems and methods for measuring a surface topography of a semiconductor chip are disclosed. A disclosed system comprises a light source configured to provide low coherent light to a first beam splitter, a scanner configured to use the low coherent light reflected from the first beam splitter to scan positions on a surface of a semiconductor chip, a second beam splitter configured to receive reflected signals from the positions on the surface of the semiconductor chip, a detector configured to detect interference signals from a first output of the second beam splitter, wherein each of the interference signals corresponds to a respective one of the positions, and a spectrometer configured to detect spectrum signals from a second output of the second beam splitter, wherein each of the spectrum signals corresponds to the respective one of the positions.

Disclosed are various systems and methods of using interferometry to measure the tear film for disease prediction and treatment. A point-by-point scan of a corneal surface of an eye is obtained from an interferometry system, including at least an interference signal. Next, a large field-of-view of the corneal surface is obtained from an objective lens with a curved focal plane matched to a curvature of the corneal surface. Subsequently, motion correction is performed on the point-by-point scan. Then, noise is filtered from the interference signal. A tear film lipid layer signal and a precorneal tear film signal are separated from the filtered interference signal. Later, a best fit frequency for the tear film lipid layer signal and the precorneal tear film signal are determined. Then, a thickness of the tear film lipid layer and the precorneal tear film are determined based at least in part on the best fit frequency.

An interferometer for the measurement of a surface or an optical thickness of an optically smooth test object is provided, wherein the interferometer is configured to illuminate the optically smooth test object simultaneously with a plurality of object waves, which have different wavelengths from one another, and to superimpose the object waves deformed by the illuminated test object onto coherent reference waves on an image capture device, and to spectrally decompose the interferograms resulting from the superposition into wavelength-specific partial interferograms.

An optical distance measurer includes: a beam splitter splitting a laser beam and outputting as measurement light and reference light; a measurement light beam splitter splitting the measurement light and outputting as first measurement light and second measurement light; a reference light beam splitter splitting the reference light and outputting as first reference light and second reference light; a first optical system having a first Rayleigh length, the first optical system emitting the first measurement light to a target object; and a second optical system having a second Rayleigh length different from the first Rayleigh length, the second optical system emitting the second measurement light to the target object; a first receiver receiving the first reference light and first reflection light that is the first measurement light reflected by the target object and outputting a first receiving signal indicating the first reference light and the first reflection light; and a second receiver receiving the second reference light and second reflection light that is the second measurement light reflected by the target object and outputting a second receiving signal indicating the second reference light and the second reflection light.