Various optical systems equipped with diode laser light sources are discussed in the present application. One example system includes a diode laser light source for providing a beam of radiation. The diode laser has a spectral output bandwidth when driven under equilibrium conditions. The system further includes a driver circuit to apply a pulse of drive current to the diode laser. The pulse causes a variation in the output wavelength of the diode laser during the pulse such that the spectral output bandwidth is at least two times larger the spectral output bandwidth under the equilibrium conditions.

Exemplary embodiments of the present disclosure include a combined catheter-based optical coherence tomography-two-photon luminescence (OCT-TPL) imaging system. Exemplary embodiments further include methods to detect, and further characterize the distribution of cellular components (e.g., macrophage, collagen/elastin fiber, lipid droplet) in thin-cap fibroatheromas with high spatial resolution in vivo.

An apparatus can be provided which can include a laser arrangement which can be configured to provide a laser radiation, and can include an optical cavity. The optical cavity can include a dispersive optical first arrangement which can be configured to receive and disperse at least one first electro-magnetic radiation so as to provide at least one second electro-magnetic radiation. Such cavity can also include an active optical modulator second arrangement which can be configured to receive and modulate the at least one second radiation so as to provide at least one third electro-magnetic radiation. The optical cavity can further include a dispersive optical third arrangement which can be configured to receive and disperse at least one third electro-magnetic radiation so as to provide at least one fourth electro-magnetic radiation. For example, actions by the first, second and third arrangements can cause a spectral filtering of the fourth electro-magnetic radiation(s) relative to the first electro-magnetic radiation(s). The laser radiation can be associated with the fourth radiation(s), and a wavelength of the laser radiation can be controlled by the spectral filtering caused by the actions by the first, second and third arrangements.

A shape measurement method of the present invention includes: a step of irradiating a measurement object with an optical pulse train in which a plurality of optical pulses that have predetermined frequency distributions on a time axis are disposed chronologically in numerical order; and a step of measuring an optical shape of the measurement object in accordance with a correspondent relation between numbers of the optical pulses of a plurality of detection target optical pulse trains after the emitted optical pulse train acts on the measurement object and a correspondent relation between the frequency distributions in the optical pulses.

The invention relates to a method and system for monitoring at least one parameter of an object. There is provided an imaging system for monitoring at least one parameter of movement of a moving object, the system comprises at least one imaging unit comprising an optical transformer configured and operable for applying spatial image space transformation of at least one parameter of movement into geometric relation, by translating different components of six degrees of freedom of movement in a three-dimensional space into a lateral translation; wherein the imaging unit is configured and operable for imaging the moving object on an image plane and generating image data indicative of the moving object in an x-y plane; the imaging system generating motion data indicative of the six degrees of freedom of movement.

A method for identifying three entangled photons includes generating a set of first, second, and third entangled photons correlated in time and interfering the first and second entangled photons based on a difference between a first optical path from an output of an optical source that generates the first entangled photon to a first optical input to an interferometric beam splitter and a second optical path from an output of the optical source that generates the second entangled photon to a second input of the interferometric beam splitter. A first electrical signal is generated in response to detection of a first photon generated by the interfering of the first and second entangled photons. A second electrical signal is generated in response to detection of a second photon generated by the interfering of the first and second entangled photons. A third electrical signal is generated in response to detection of the third entangled photon. The first photon coincidence is determined from the first, second and their electrical signals, thereby identifying three entangled photons.

Systems, methods and apparatuses are used for monitoring material processing using imaging signal density calculated for an imaging beam directed to a workpiece or processing region, for example, during inline coherent imaging (ICI). The imaging signal density may be used, for example, to monitor laser and e-beam welding processes such as full or partial penetration welding. In some examples, the imaging signal density is indicative of weld penetration as a result of reflections from a keyhole floor and/or from a subsurface structure beneath the keyhole. The monitoring may include, for example, automated pass/fail or quality assessment of the welding or material processing or parts produced thereby. The imaging signal density may also be used to control the welding or material processing, for example, using imaging signal density data as feedback. The imaging signal density may be used alone or together with other measurements or metrics, such as distance or depth measurements.

A distance measurement device according to the present disclosure includes: a light source configured to emit pulsed laser light; a superimposition portion configured to superimpose reflection light obtained by reflection of the pulsed laser light by an object to be measured and reference light that is the pulsed laser light; a saturation output portion, on which the reference light and the reflection light superimposed on each other are made incident, configured to output light having a saturated light quantity when incident light reaches a predetermined light quantity due to superimposition of pulses of the reflection light and the reference light; and a light-receiving portion configured to receive the light outputted from the saturation output portion.

A signal processing method executed by a signal processing device, includes performing a phase connection process on a position in a space and a phase value at each of a plurality of times, performing outlier correction of a phase value for each position in the space in a predetermined direction of the space at a predetermined time among the plurality of times based on a result of the phase connection process, and correcting a phase value at a time other than the predetermined time for each of correction target positions among positions in the space.

Various optical systems equipped with diode laser light sources are discussed in the present application. One example system includes a diode laser light source for providing a beam of radiation. The diode laser has a spectral output bandwidth when driven under equilibrium conditions. The system further includes a driver circuit to apply a pulse of drive current to the diode laser. The pulse causes a variation in the output wavelength of the diode laser during the pulse such that the spectral output bandwidth is at least two times larger the spectral output bandwidth under the equilibrium conditions.