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At least 433 records · Page 24

Video display engineering and optimization system

A video display engineering and optimization CAD simulation system for designing a LCD display integrates models of a display device circuit, electro-optics, surface geometry, and physiological optics to model the system performance of a display. This CAD system permits system performance and design trade-offs to be evaluated without constructing a physical prototype of the device. The systems includes a series of modules which permit analysis of design trade-offs in terms of their visual impact on a viewer looking at a display.

Larimer, James↗

Frequency doubled, cavity dumped feedback laser

Higher efficiency in cavity dumping and frequency doubling in a laser used to produce modulated output beam pulses is achieved by deflecting light out of the resonant cavity to a third mirror through a frequency doubler using an electro-optic modulator and a polarizing beamsplitter in the resonant cavity, or using just an acousto-optic modulator to deflect light out of the laser cavity in response to a control signal (electric or acoustic). The frequency doubler in front of the third mirror rotates the frequency doubled light so that it will pass out of the laser cavity through the polarizing beamsplitter, while undoubled frequency light is reflected by the polarizing beamsplitter back into the gain medium of the laser. In the case of using a type-II frequency doubler, a dichroic beamsplitter deflects out the frequency doubled light and passes the undoubled frequency light to the polarizing beamsplitter for return to the laser gain medium. If an acousto-optic modulator is used, it deflects light out of the primary laser cavity, so a polarizing beamsplitter is not needed, and only a dichroic beamsplitter is needed to separate frequency doubled light out of the path from the third mirror.

Sipes, Jr., Donald L.↗

Method of making a semiconductor device assembly

The invention is a semiconductor device assembly and method of making the same. A mounting plate has positioning means for positioning the plate relative to a header, a first mounting surface of the plate is attached to the header and a semiconductor device is attached to a second mounting surface of the mounting plate. The assembly is made by forming the mounting plate, positioning the mounting plate relative to the header by the positioning means, attaching the first mounting surface to the header and the semiconductor device to the second mounting surface. Another method of making the assembly is by defining and etching a mounting plate and attaching the first mounting surface to the header and the semiconductor device to the second mounting surface. This assembly and process provides an efficient means for mounting semiconductor devices and in particular electro-optic devices such as lasers.

Dholakia, Anil R.↗

Automated mass spectrometer analysis system

An automated mass spectrometer analysis system is disclosed, in which samples are automatically processed in a sample processor and converted into volatilizable samples, or their characteristic volatilizable derivatives. Each volatizable sample is sequentially volatilized and analyzed in a double focusing mass spectrometer, whose output is in the form of separate ion beams all of which are simultaneously focused in a focal plane. Each ion beam is indicative of a different sample component or different fragments of one or more sample components and the beam intensity is related to the relative abundance of the sample component. The system includes an electro-optical ion detector which automatically and simultaneously converts the ion beams, first into electron beams which in turn produce a related image which is transferred to the target of a vidicon unit. The latter converts the images into electrical signals which are supplied to a data processor, whose output is a list of the components of the analyzed sample and their abundances. The system is under the control of a master control unit, which in addition to monitoring and controlling various power sources, controls the automatic operation of the system under expected and some unexpected conditions and further protects various critical parts of the system from damage due to particularly abnormal conditions.

Boettger, Heinz G.↗

Semiconductor device assembly and method of making same

The invention is a semiconductor device assembly and method of making the same. A mounting plate has positioning means for positioning the plate relative to a header, a first mounting surface of the plate is attached to the header and a semiconductor device is attached to a second mounting surface of the mounting plate. The assembly is made by forming the mounting plate, positioning the mounting plate relative to the header by the positioning means, attaching the first mounting surface to the header and the semiconductor device to the second mounting surface. Another method of making the assembly is by defining and etching a mounting plate and attaching the first mounting surface to the header and the semiconductor device to the second mounting surface. This assembly and process provides an efficient means for mounting semiconductor devices and in particular electro-optic devices such as lasers.

Dholakia, Anil R.↗

A Method of Monitoring Non-Resonant Raman Lidar Returns During Daylight Hours

A method for using non-resonant Raman lidar during daytime hours is presented. A dual (or quadruple) arrangement of electro-optical channels is set up in the lidar receiver. Each channel contains its own optical spectral response as determined by an appropriate set of interference filters. The incoming signal is split and fed into two channels, filtered (simultaneously) and then inserted into the input terminals of an operational amplifier. The difference signal is selected and amplified whereas the common portion of the signal is highly attenuated (Common Mode Re.jection Ratio = 75-80db). For the present hardware, daylight intensities 10(exp 2)-10(exp 3) times Raman signals are received simultaneously. Mean values of intensities of daylight signals which give rise to a constant differences merely shift the value of the measured variable at the ground. These mean value signals have their common part highly attenuated. The differences of the fluctuation portions of the daylight signal represents a noise signal. Identical (space-time) optical paths for each component of the daylight signal produce the same fluctuational spectra in each channel. Hence noise levels, much less than signal levels, are anticipated. First a N2-H2 ) signal pair is differenced. Then an N2-O2 pair is differenced and used for instrumental normalization purposes. Signal levels to be encountered are quite well known as a result of prior field work. Improved optical design of laser system can reduce mean value of daylight intensities by 10(exp 2). Thus the mean daylight intensity can be set equal to the expected signal levels by more advanced optical design. Performance characteristics of photomultiplier pairs are discussed in this connection.

Cooney, John↗

A New Class Of Opto-Electronic Oscillators (OEO) for Microwave Signal Generation and Processing

A new class of oscillators based on photonic devices is presented. These opto-electronic oscillators (OEO's) generate microwave oscillation by converting continuous energy from a light source using a feedback circuit which includes a delay element, and electro-optic switch, and a photodetector. Different configurations of OEO's are presented, each of which may be applied to a particular application requiring ultra-high performance, or low cost and small size.

oscillators↗

Space applications.

Laser in space application, discussing electro- optical devices

ELECTRO-OPTICS↗

Surface Plasmon Tunable Filter and Spectrometer-on-a-Chip

Surface plasmon tunable filter (SPTF) is a new technology invented in Jet Propulsion Lab. When a white light is incident on a metal/air/metal structure, in certain condition, surface plasmon waves can be excited at one metal/air material interface; those photons in surface plasmon resonances wavelength range will be converted into the energy of free electrons in the metal than coupled into the other metal film, and re-radiate out the color light.

Surface↗

Electronically Tunable Color Filter with Surface Plasmon Waves

Last year, I had reported a novel phenomenon of voltage-induced color-selective absorption with surface plasmons (Appl. Phys. Lett. 67, 2749)...A prototype ( of a tunable notch filter) has been built using liquid crystal as the EO material.

Surface↗