Abstract:
A tracking system utilizing an excited state atomic line filter. The filter includes a metal vapor cell having an optical entrance port and an optical exit port and containing a metal vapor having a first excited energy state with a resonant frequency, and a second excited energy state. The cell has an absorption line, at or near a desired filter wavelength. The platform to be tracked, which could be an un-manned aerial vehicle has a beacon laser system located on it for producing a beacon laser beam at a wavelength within the narrow spectral band. The present invention solves the problem of lack of ground state resonant lines in at wavelengths substantially longer than those of visible light. Atomic line filters of the Faraday or Voigt crossed polarizer type are provided in which alkali metal atomic vapor in a vapor cell is excited with a pump beam to an intermediate excited state where a resonant absorption line, at a desired wavelength, is available. A magnetic field is applied to the cell producing a polarization rotation for polarized light at wavelengths near the resonant absorption lines. Thus, all light is blocked by the cross polarizers except light near one of the spaced apart resonant lines. However, the polarization of light at certain wavelengths near the resonant is rotated in the cell and therefore passes through the output polarizer.
Abstract:
An excited state atomic line filter. The present invention solves the problem of lack of ground state resonant lines in at wavelengths substantially longer than those of visible light. Atomic line filters of the Faraday or Voigt crossed polarizer type are provided in which alkali metal atomic vapor in a vapor cell is excited with a pump beam to an intermediate excited state where a resonant absorption line, at a desired wavelength, is available. A magnetic field is applied to the cell producing a polarization rotation for polarized light at wavelengths near the resonant absorption lines. Thus all light is blocked by the cross polarizers except light near one of the spaced apart resonant lines. However, the polarization of light at certain wavelengths near the resonant is rotated in the cell and therefore passes through the output polarizer.
Abstract:
A process for the long term or permanent prevention of growth of unwanted hair. The upper portions of hair ducts (i.e. portions near the skin surface) in a section of skin are infiltrated with a contaminant having a high absorption at at least one frequency band of light. The skin is then illuminated using a process having at least two distinct phases. In a "mechanical" phase the skin section is illuminated (e.g., by a laser) with at least one short pulse of light sufficient to cause tiny explosions in the contaminant forcing portions of the contaminant more deeply into the hair ducts. During a "thermal" phase the skin section is then illuminated so as to heat the contaminant substantially without further explosion or vaporization of the contaminant. The hot contaminant heats portions of the skin tissue immediately surrounding the contaminant to a temperature high enough and for a long enough period of time to devitalize the tissue. The process may also include a "cleanup" phase, during which the skin section is illuminated with a few short pulses of light to cause additional explosions in and vaporization of portions of the contaminant then remaining in the ducts and additional damage to the skin tissue immediately surrounding the contaminant.
Abstract:
A tracking system utilizing an excited state atomic line filter. The filter includes a metal vapor cell having an optical entrance port and an optical exit port and containing a metal vapor having a first excited energy state with a resonant frequency, and a second excited energy state. The cell has an absorption line, at or near a desired filter wavelength. The platform to be tracked, which could be an un-manned aerial vehicle has a beacon laser system located on it for producing a beacon laser beam at a wavelength within the narrow spectral band. The present invention solves the problem of lack of ground state resonant lines in at wavelengths substantially longer than those of visible light. Atomic line filters of the Faraday or Voigt crossed polarizer type are provided in which alkali metal atomic vapor in a vapor cell is excited with a pump beam to an intermediate excited state where a resonant absorption line, at a desired wavelength, is available. A magnetic field is applied to the cell producing a polarization rotation for polarized light at wavelengths near the resonant absorption lines. Thus, all light is blocked by the cross polarizers except light near one of the spaced apart resonant lines. However, the polarization of light at certain wavelengths near the resonant is rotated in the cell and therefore passes through the output polarizer.
Abstract:
An excited state atomic line filter. The present invention solves the problem of lack of ground state resonant lines in at wavelengths substantially longer than those of visible light. Atomic line filters of the Faraday or Voigt crossed polarizer type are provided in which alkali metal atomic vapor in a vapor cell is excited with a pump beam to an intermediate excited state where a resonant absorption line, at a desired wavelength, is available. A magnetic field is applied to the cell producing a polarization rotation for polarized light at wavelengths near the resonant absorption lines. Thus all light is blocked by the cross polarizers except light near one of the spaced apart resonant lines. However, the polarization of light at certain wavelengths near the resonant is rotated in the cell and therefore passes through the output polarizer.
Abstract:
Methods of applying laser light to the skin, and apparatus therefor, include methods for removing hair, for synchronizing hair growth, for stimulating hair growth, for treating Herpes virus, for reducing sweat and body odor, for in situ formation of a chromophore in hair ducts, for reducing light loss at the skin surface, for grafting of hair stem cells, and for removing keloid or hypertrophic scars. The hair removal methods include controlling the proportions of photomechanical and photothermal damage by selection of laser parameters, chromophore particle size and/or pulse duration, with optional dynamic skin cooling. Additional hair removal methods include infiltrating a photoactivated drug into hair ducts and exposing the skin to sunlight or administering an anti-proliferative agent into hair ducts, for example, by encapsulating the anti-proliferative agent in a slow release vehicle. The methods of treating Herpes virus, reducing sweat or body odor, and removing keloid or hypertrophic scars include infiltrating a light-absorbing contaminant into hair ducts or other openings in the skin and illuminating the contaminated skin section. The methods for stimulating hair growth include grafting of cloned auto hair stem cells the hair ducts or administering methionine to a skin section to increase hair growth. Apparatus useful in performing these methods include devices for making a smooth optical boundary between skin and air or for dividing a light beam into a plurality of smaller light beams, and dressings for use before, during and after laser illumination.