Abstract: A terahertz generating assembly generally includes a light emitting device that is configured to generate at least one pulsed light beam. A first dispersion member is positioned proximate to the light emitting device, wherein the first dispersion member is configured to facilitate a temporal dispersion of the light beam. A second dispersion member is positioned proximate to the first dispersion member and to the light emitting device, wherein the second dispersion member is configured to facilitate a spatial dispersion of the light beam. A lens is positioned proximate to each of the first and second dispersion members, wherein the lens is configured to focus the temporal and spatial dispersions to produce at least one moving spot of light. At least one waveguide is positioned proximate to the lens, wherein the waveguide is configured to apply a biased voltage to the spot of light to generate pulsed terahertz radiation.

Abstract: Various embodiments are directed to systems and methods for imaging subsurface features of a semiconductor object comprising a first region having a first doping property and a second region having a second doping property. The semiconductor object may comprise subsurface features and material between a surface of the semiconductor object and the subsurface features. The material may have an index of refraction that is greater than an index of refraction of a surrounding medium in contact with the surface of the semiconductor object. For example, a system may comprise an imaging device comprising an objective. The imaging device may be sensitive to a first wavelength. The system may also comprise an illumination source to emit illumination substantially at the first wavelength. The illumination may be directed towards the surface of the semiconductor object at a first angle relative to a normal of the surface. The first angle is greater than an acceptance angle of the objective of the imaging device.

Abstract: Various embodiments are directed to systems and methods for imaging subsurface features of a semiconductor object comprising a first region having a first doping property and a second region having a second doping property. The semiconductor object may comprise subsurface features and material between a surface of the semiconductor object and the subsurface features. The material may have an index of refraction that is greater than an index of refraction of a surrounding medium in contact with the surface of the semiconductor object. For example, a system may comprise an imaging device comprising an objective. The imaging device may be sensitive to a first wavelength. The system may also comprise an illumination source to emit illumination substantially at the first wavelength. The illumination may be directed towards the surface of the semiconductor object at a first angle relative to a normal of the surface. The first angle is greater than an acceptance angle of the objective of the imaging device.

Abstract: An optical transducer, such as used in an ultrasound system, includes a signal laser which generates an optical signal the frequency of which varies in correspondence with acoustic energy incident on the transducer. An optical cavity in the signal laser is disposed such that incident acoustic energy causes compression and rarefaction of the optical cavity, and this displacement varies optical frequency generated by the laser. A laser pump coupled to the lasing medium is adapted to apply selected levels of excitation energy appropriate to the generation and detection of acoustic pulses. The signal laser alternatively is adapted such that the refractive index of the optical cavity is varied in correspondence with the incident acoustic energy to modulate the optical frequency of the light generated by the signal laser.

Abstract: This invention relates to lasers which produce a high average power. Such structures of this type, generally, produce the high average power intensity having a high peak intensity at a wavelength near 530 nm.