An apparatus and method are disclosed for actinic inspection of semiconductor masks intended for extended ultraviolet (EUV) lithography, or similar objects, with feature sizes less than 100 nm. The approach uses a coherent light source with wavelength less than 120 nm. Inside a vacuum system, an optical system directs the light to an object, i.e., the mask or mask blank, and directs the resulting reflected or transmitted light to an imaging sensor. A computational system processes the imaging sensor data to generate phase and amplitude images of the object. The preferred imaging modality, a form of digital holography, produces images of buried structures and phase objects, as well as amplitude or reflectance images, with nanometer resolution less than or equal to the feature size of the mask.

A Free Electron Laser source includes: a fiber-based laser having a plurality of amplifying fibers wherein an initial laser pulse is distributed and amplified, and element for grouping together the elementary pulses amplified in the fiber in order to form an a single amplified global laser pulse; a laser plasma accelerator wherein the global laser pulse generates relativistic electron beams, a beam focusing system transporting electron beams from the laser plasma accelerator, an undulator wherein relativistic electron beams generate an electromagnetic beam, and a beam separator system, wherein the electron beam and the electromagnetic beam are separated.

A system is disclosed which includes a laser which has a calibrated optical power and a calibrated tolerance. The system includes a driving circuit configured to generate a first current pulse and a second current pulse. The system includes a primary observer module configured to observe a first and second primary input. The system includes one or more secondary observer modules configured to observe one or more first and one or more second secondary inputs. The system includes a controller communicatively coupled to the laser, driving circuit, primary observer module, and the one or more secondary observer modules. The controller is configured to receive an information packet, calculate an optical power, determine a deviation of the optical power from the calibrated optical power, compare the deviation with the calibrated tolerance, and perform an action if the deviation exceeds the calibrated tolerance.

An optical amplification apparatus includes an optical amplification medium, having a gain in a wavelength band of signal light, configured to receive the signal light; excitation light introduction means for introducing, into the optical amplification medium, excitation light to excite the optical amplification medium; and residual excitation light introduction means for introducing, into the optical amplification medium, residual excitation light output from the optical amplification medium, the residual excitation light having a wavelength component of the excitation light, wherein the residual excitation light introduction means includes, on a side of one end of the optical amplification medium, residual excitation light multiplexing means for multiplexing the signal light and the residual excitation light, and on a side of another end of the optical amplification medium, space propagation type wavelength demultiplexing means for wavelength-demultiplexing the signal light and the residual excitation light by means of a spatial optical system.

An optical amplification apparatus includes an optical amplification medium, having a gain in a wavelength band of signal light, configured to receive the signal light; excitation light introduction means for introducing, into the optical amplification medium, excitation light to excite the optical amplification medium; and residual excitation light introduction means for introducing, into the optical amplification medium, residual excitation light output from the optical amplification medium, the residual excitation light having a wavelength component of the excitation light, wherein the residual excitation light introduction means includes, on a side of one end of the optical amplification medium, residual excitation light multiplexing means for multiplexing the signal light and the residual excitation light, and on a side of another end of the optical amplification medium, space propagation type wavelength demultiplexing means for wavelength-demultiplexing the signal light and the residual excitation light by means of a spatial optical system.

A system incorporating safety features, for optical power transmission to receivers, comprising an optical resonator having end reflectors and a gain medium, a driver supplying power to the gain medium, and controlling its small signal gain, a beam steering apparatus and a controller to control at least the beam steering apparatus and the driver. The controller responds to a safety risk occurring in the system, by outputting a command to change at least some of the small signal gain of the gain medium, the radiance of the optical beam, the power supplied by the driver, the scan speed or the scan direction and position of the beam steering apparatus, or to register the scan pose which defines the location of said optical-to-electrical power converter. The controller may also ensure a high overall radiance efficiency, and may warn of transmitted power not received by a targeted receiver.

A system incorporating safety features, for optical power transmission to receivers, comprising an optical resonator having end reflectors and a gain medium, a driver supplying power to the gain medium, and controlling its small signal gain, a beam steering apparatus and a controller to control at least the beam steering apparatus and the driver. The controller responds to a safety risk occurring in the system, by outputting a command to change at least some of the small signal gain of the gain medium, the radiance of the optical beam, the power supplied by the driver, the scan speed or the scan direction and position of the beam steering apparatus, or to register the scan pose which defines the location of said optical-to-electrical power converter. The controller may also ensure a high overall radiance efficiency, and may warn of transmitted power not received by a targeted receiver.

A system including an electron beam source for providing an electron beam and at least one undulator system configured to produce free-electron laser (FEL) radiation is described. The undulator system includes undulators and at least one optical section between the undulators. The undulators are configured to induce the electron beam to microbunch and radiate coherently. The optical section(s) are configured to operate on the electron beam and the FEL radiation generated by the electron beam.

A light source for high power coherent light can include multiparticle relativistic bunches of electrons generating high intensity propagating fields. Coherent emission between electrons may also be utilized. The source may be independent of any medium or media to remove all constraints on the wavelength of the light emitted. And at least a portion of a single alternating magnetic field for accelerating the electron bunches can be included. The color or wavelength of the produced light can be determined solely by the parameters of the electron bunches and the alternating field. The source can be used for imaging, such as medical imaging or for security, including concealed weapons, and for quality control.

Provided is a method of generating a squeezed quantum illumination light source, including generating a dual mode squeezed light source including a signal mode and an idler mode, obtaining a degree of additional squeezing for the dual mode squeezed light source based on object information, determining a squeezing angle and a degree of operation that satisfy the degree of additional squeezing for each of the signal mode and the idler mode, and squeezing the dual mode squeezed light source based on the squeezing angle and the degree of operation, and provided is a quantum radar device using the squeezed quantum illumination light source.