摘要:
Solid state laser gain media of segmented construction are composed of at least two segments of a doped crystalline laser host which are arranged in crystallographic alignment, wherein the dopant concentration varies from segment to segment to provide gradient doping levels for reducing thermally generated stress/strain in the lasing operation.
摘要:
An active imaging system for viewing targets with a high degree of range resolution of approximately one foot. The imaging system utilizes a laser pulse which passes through an electro-optical pulse slicer which creates a sharp leading edge and/or a sharp falling edge on the laser pulse. The laser pulse travels to the target under observation, illuminates and reflects off of the target and returns to a camera. A target is viewed only during the time all or a portion of the returning laser pulse overlaps the time the camera shutter gate is open. The imaging system is particularly suited for determining depth information about a target by varying the time relationship when the returning laser pulse is received by the camera.
摘要:
Solid state laser gain media of the composition Cr.sup.+3 :XYZF.sub.6 wherein X is an alkali metal ion; Y is an alkaline earth metal ion, Cd.sup.+2 or Mg.sup.+2 ; and Z is Al.sup.+3, Ga.sup.+3 or Sc.sup.+3 are provided with gradient Cr doping levels for reducing thermally generated stress/strain in the lasing operation.
摘要:
A mount for suspending a laser medium has a cross section profile. The mount is configured to conduct heat away from the laser medium without imparting undue stress. The mount includes a laser host medium having a first cross section profile. A heat sink defines a bore. The bore has a second cross section profile configured to envelop the first cross section profile and further defines a generally uniform interspace between the first cross section profile and second first cross section profile. An amalgam of a mercury soluble metal is formed to substantially fill the interspace to support the laser host medium.
摘要:
A magnetic core-coil assembly generates an ignition event in a spark ignition internal combustion system having at least one combustion chamber. The assembly comprises a magnetic core of amorphous metal having a primary coil for low voltage excitation and a secondary coil for a high voltage output to be fed to a spark plug. A high voltage is generated in the secondary coil within a short period of time following excitation thereof. The assembly senses spark ignition conditions in the combustion chamber to control the ignition event. The assembly is constructed from sub-assembly parts that can be manufactured with existing machines at reasonable cost. The assembly is then potted in a housing consisting of a high temperature polymer.
摘要:
Taggants can be incorporated into or onto value documents. The taggants comprise a crystalline taggant doped with two rare earth ions. The substrate or printed matter into which the taggant can be incorporated has a minimal absorption infrared wavelength window and the taggant is excited by incident infrared radiation in this wavelength range. Suitable first rare earth ions function as efficient broad band absorbers of incident infrared radiation and passes energy non-radiatively to a second rare earth ion, which emits infrared radiation at a wavelength greater than the incident infrared radiation. The emitted infrared radiation is also in the minimal absorption transmission window of the printed matter or the substrate into which the taggant is incorporated. Methods of authenticating the value document include detection of the emitted radiation at pre-determined values.
摘要:
Cascading phosphors are described herein that produce emissions when they are excited by incident radiation. The cascading phosphors can be applied to articles, and can be useful in authenticating the article. The cascading phosphors include a host and at least three active ions.
摘要:
An optical diffuser plate disposed between a flashlamp and a solide state laser within a solid state laser pump chamber. The optical diffuser plate acts as a homogenizer of the pump light to reduce pumping inhomogeneities inherent with specular reflectors, while at the same time providing an efficient energy transfer from the flashlamp to the solid state laser. The optical diffuser plate can also filter out pump light below critical wavelengths that can be detrimental to the solid state laser.
摘要:
Method and apparatus for separating a mixed frequency light beam, particularly a laser light beam, into its different frequency components by impinging it on a first surface of an optical slab which reflects one component but transmits another, and re-directing the reflected component via a roof prism to a second surface of the slab which is adjacent to and positioned 90.degree. to the first surface, to obtain a reflected beam which is co-directional with the mixed beam, but stripped of the transmitted component.
摘要:
A magnetic core-coil assembly generates an ignition event in a spark ignition internal combustion system having at least one combustion chamber. The assembly comprises a magnetic core of amorphous metal having a primary coil for low voltage excitation and a secondary coil for a high voltage output to be fed to a spark plug. A high voltage is generated in the secondary coil within a short period of time following excitation thereof. The assembly senses spark ignition conditions in the combustion chamber to control the ignition event. The assembly is constructed from sub-assembly parts that can be manufactured with existing machines at reasonable cost.