1202 results about "Pulse duration" patented technology

A method of tailoring conformality of a film deposited on a patterned surface includes: (I) depositing a film by PEALD or pulsed PECVD on the patterned surface; (II) etching the film, wherein the etching is conducted in a pulse or pulses, wherein a ratio of an etching rate of the film on a top surface and that of the film on side walls of the patterns is controlled as a function of the etching pulse duration and the number of etching pulses to increase a conformality of the film; and (III) repeating (I) and (II) to satisfy a target film thickness.

An ultra wide bandwidth, high speed, spread spectrum communications system uses short wavelets of electromagnetic energy to transmit information through objects such as walls or earth. The communication system uses baseband codes formed from time shifted and inverted wavelets to encode data on a RF signal. Typical wavelet pulse durations are on the order of 100 to 1000 picoseconds with a bandwidth of approximately 8 GHz to 1 GHz, respectively. The combination of short duration wavelets and encoding techniques are used to spread the signal energy over an ultra wide frequency band such that the energy is not concentrated in any particular narrow band (e.g. VHF: 30-300 MHz or UHF: 300-1000 MHz) and is not detected by conventional narrow band receivers so it does not interfere with those communication systems. The use of pulse codes composed of time shifted and inverted wavelets gives the system according to the present invention has a spatial resolution on the order of 1 foot which is sufficient to minimize the negative effects of multipath interference and permit time domain rake processing.

Methods are provided for treating prostate glands or other targeted soft tissue using a solid-state laser. The laser can be operated to generate a pulsed output beam having pulse durations of between 0.1 and 500 milliseconds. The output beam is delivered to the targeted tissue through an optical fiber, preferably terminating in a side-firing probe or diffusing tip. By operating the laser in a long-duration pulse mode, charring of the targeted tissue is initiated quickly, thereby increasing ablation rates and reducing overall procedure time.

A laser-based method and apparatus for corneal surgery. The present invention is intended to be applied primarily to ablate organic materials, and human cornea in particular. The invention uses a laser source which has the characteristics of providing a shallow ablation depth (0.2 microns or less per laser pulse), and a low ablation energy density threshold (less than or equal to about 10 mJ / cm2), to achieve optically smooth ablated corneal surfaces. The preferred laser includes a laser emitting approximately 100–50,000 laser pulses per second, with a wavelength of about 198–300 nm and a pulse duration of about 1–5,000 picoseconds. Each laser pulse is directed by a highly controllable laser scanning system. Described is a method of distributing laser pulses and the energy deposited on a target surface such that surface roughness is controlled within a specific range. Included is a laser beam intensity monitor and a beam intensity adjustment means, such that constant energy level is maintained throughout an operation. Eye movement during an operation is corrected for by a corresponding compensation in the location of the surgical beam. Beam operation is terminated if the laser parameters or the eye positioning is outside of a predetermined tolerable range. The surgical system can be used to perform surgical procedures including removal of corneal scar, making incisions, cornea transplants, and to correct myopia, hyperopia, astigmatism, and other corneal surface profile defects.