Methods and devices are described for performing an all-phase measurement of an ultra-fast laser pulse having a spectral range of greater than one octave. The ultra-fast laser pulse may be split into a first beam comprising a fundamental light with a wavelength λ.sub.0 and a second beam comprising a light with a wavelength 2λ.sub.0. The light with the wavelength 2λ.sub.0 may be frequency doubled to a light with a wavelength λ.sub.0 to generate an interference with the fundamental light. Fourier transform may be performed on an interference spectrum of the interference, and a relative envelope delay (RED) between the fundamental light and the frequency doubled light and a carrier envelope phase (CEP) may be acquired based on a result of the Fourier transform.

Methods and devices are described for performing an all-phase measurement of an ultra-fast laser pulse having a spectral range of greater than one octave. The ultra-fast laser pulse may be split into a first beam comprising a fundamental light with a wavelength λ.sub.0 and a second beam comprising a light with a wavelength 2λ.sub.0. The light with the wavelength 2λ.sub.0 may be frequency doubled to a light with a wavelength λ.sub.0 to generate an interference with the fundamental light. Fourier transform may be performed on an interference spectrum of the interference, and a relative envelope delay (RED) between the fundamental light and the frequency doubled light and a carrier envelope phase (CEP) may be acquired based on a result of the Fourier transform.

A spiral phase plate, according to one embodiment, for generating a Laguerre Gaussian beam by reflecting an incident beam emitted from a light source, may comprise: a first quadrant area in which the step height increase rate per unit angle decreases progressively in one direction from the point with the lowest step height to the point with the highest step height; and a second quadrant area in which the step height increase rate per unit angle increases progressively in the one direction.

A spiral phase plate, according to one embodiment, for generating a Laguerre Gaussian beam by reflecting an incident beam emitted from a light source, may comprise: a first quadrant area in which the step height increase rate per unit angle decreases progressively in one direction from the point with the lowest step height to the point with the highest step height; and a second quadrant area in which the step height increase rate per unit angle increases progressively in the one direction.

A method for super-resolution photoacoustic microscopy of an object. The method includes optically exciting the object according to a plurality of excitation patterns utilizing a digital micromirror device (DMD), receiving a plurality of acoustic waves propagated from the object due to optically exciting the object, reconstructing each of a plurality of photoacoustic (PA) images from a respective acoustic wave of the plurality of acoustic waves, and obtaining a super-resolution PA image of the object from the plurality of PA images by applying a frequency domain reconstruction method to the plurality of PA images. Each of the plurality of acoustic waves are associated with a respective excitation pattern of the plurality of excitation patterns.

A method for super-resolution photoacoustic microscopy of an object. The method includes optically exciting the object according to a plurality of excitation patterns utilizing a digital micromirror device (DMD), receiving a plurality of acoustic waves propagated from the object due to optically exciting the object, reconstructing each of a plurality of photoacoustic (PA) images from a respective acoustic wave of the plurality of acoustic waves, and obtaining a super-resolution PA image of the object from the plurality of PA images by applying a frequency domain reconstruction method to the plurality of PA images. Each of the plurality of acoustic waves are associated with a respective excitation pattern of the plurality of excitation patterns.

The present disclosure relates to a coherent aperture array system for steering an optical source beam. The system may have a plurality of spaced apart, steerable emitters each being able to be mechanically aimed at a remote target location to steer portions of the source beam toward the target location. Each steerable emitter has a subaperture controllable independently of a remaining reflective surface of its associated steerable emitter, to receive and reflect a subportion of the source beam portion. The subportion forms a sense beam which is reflected toward a phase imaging system. A separate reference beam is created from the portion of the source beam travelling toward each steerable emitter. Each sense beam and each reference beam are thus associated uniquely with one of the steerable emitters. A phase imaging system is responsive to each of the reference beams and the sense beams, and determines phase differences between the portions of the source beam being transmitted from each steerable emitter.

An apparatus for combining a plurality of coherent laser beams includes a splitting device for splitting an input laser beam into the plurality of coherent laser beams, a plurality of phase setting devices for adjusting a respective phase of one of the coherent laser beams, and a beam combining device for combining the coherent laser beams, which emanate from a plurality of grid positions of a grid arrangement, to form at least one combined laser beam. The beam combining device has a microlens arrangement with exactly one microlens array for forming the at least one combined laser beam.

Methods, devices and systems are described that enable improved determination of wavefront errors associated with light traveling through turbulent media, such as through the atmosphere. The described systems use a Rayleigh-Raman polychromatic laser guide star (RRPLGS) to measure the tilt at the wavelength of observation by making use of the dispersion of the refractive index of air and differential tilt measurements at multiple combinations of wavelengths based on the Rayleigh and Raman back-scattered light. The described RRPLGS systems have a number of advantages, including scalability of returned flux and flexibility in selection of short wavelengths, allowing for a combination of multiple tilt measurements, and enabling characterization of the turbulent media without relying on photons from the object of interest.

For correcting aberration-induced imaging errors of an optical system which includes an objective (14) and an adaptive optic (18), light (5) and a sample (20) are selected such that the light (5), in acting upon the sample (20), reduces a measurement signal (28) from the sample (20), wherein a relative variation of the measurement signal (28) depends on the intensity of the light (5). The measurement signal (28) from a focal area of the optical system in the sample (20) is registered over a first and a later second period of time (38, 37) to determine a first measurement value and a second measurement value. Over a third period of time (39) which overlaps with the first and/or the second period of time, the light (5) is focused into the focal area by means of the optical system. A measure value for the relative variation of the measurement signal (28) is determined from the first and the second measurement values and used in controlling the adaptive optic (18) as a metric to be optimized.