A broadband optical discriminator for determining the wavelength of received radiation which is in a narrow band is described. The received radiation is passed through a polarization spoiler, a linear polarizer, a polarization dispersion device, and a beam splitting polarizer forming two beams. The intensity of the two beams is converted into electrical signals. The electrical signals are processed to provide a signal indicative of the wavelength of the incident radiation.
Electro-Optical Modulator For Randomly Polarized Light
Electro-optical apparatus for modulating a randomly polarized light beam is disclosed. The apparatus includes an electro-optical cell and a plurality of optical elements configured to polarize the randomly polarized light beam into two light beam components and to guide the light beam components along two respectively corresponding sets of optical paths, a portion of each set of optical paths passing colinearly through a predetermined axis of the electro-optical cell. Each set of paths are combined to reform an associated portion of the randomly polarized light beam which is exited at a corresponding exit surface of the apparatus, the reformed exited portion, in each case, being a function of the energization of the electro-optical cell. In one application, the electro-optical apparatus is disposed in the optical cavity of a laser system and operative therein as a Q modulator wherein the Q of the laser cavity is dependent on the energization level of the electro-optical cell.
Dielectric Polarizer For High Average And High Peak Power Operation
A dielectric optical polarizer which is operable at high peak and average power, with greater than 95 percent transmission of the desired P polarized radiation, and also greater than 95 percent reflectance of the S polarized radiation. The polarizer comprises a radiation transmissive substrate with a first dielectric layer disposed on at least one side of the substrate. The first dielectric layer has an index of refraction higher than the substrate. A second dielectric layer of low index of refraction material is disposed atop the first dielectric layer. A third dielectric layer of the same high index of refraction material as the first layer, is disposed atop the second layer. Each of the dielectric layers is one quarter wavelength thick at the operating wavelength. The dielectric polarizer operates at a very high Brewster angle associated with the dielectric layers rather than that of the substrate.
Charge Coupled Device Circuit With Increased Signal Bandwidth
A charge coupled device (CCD) circuit suitable for low level input signals, e. g. , from a photodiode, is disclosed. A low noise bias current source directly injects a current into a metal-oxide-semiconductor (MOS) device in order to increase the transconductance of the CCD, consequently extending the bandwidth of the CCD without increasing output noise levels.
Surface Treatment Apparatus With Selective Loading
- Rockville MD, US Shane Brewer - Washington DC, US John Wentz - Rockville MD, US
International Classification:
B24B 7/18 B24B 41/04 B24B 47/06
Abstract:
A surface treatment system using motors that drive abrasive pads to treat a surface has structure that applies a force on the abrasive pad that provides a non-uniform contact pressure between the abrasive pad and the treated surface. This allows the system to treat the surface more quickly. Several structures are disclosed for applying the necessary force to the abrasive pad. In preferred embodiments, the non-uniform contact pressure results from application of torque to a motor that drives the abrasive pad.