High Brightness Excimer Lamp


Invention Summary:

An esteemed Rutgers laser physics professor has developed a miniature high brightness excimer lamp. The high brightness lamp is made of a 0.5 mm inner diameter glass tube and four straps of copper wrapped around the glass tube independently, and separated by a fixed distance. The copper leads serve as the outer electrodes in an “electrode-less” configuration (in the sense that the plasma does not come in direct contact with the electrodes) to avoid electrode erosion and contamination of the plasma with metal vapor. In this “electrode-less” design, discharged radio frequency (RF) power is capacitively coupled through the insulating wall of the tube. When RF power is applied to the electrodes, an intense plasma is generated inside the tube in the space between the electrodes. This discharge plasma, when ignited in gas mixture such as Xenon Halogen, is an intense and a highly stable source of UV radiation. A gas reservoir is used to maintain the concentration of the halogen inside the lamp to obtain a long lifetime of a completely sealed system. A convection flow of gas through the narrow tube is necessary to cool the discharge region and obtain a bright UV light. The unique design of the excimer light source provides a stable and extremely intense beam of light in a small concentrated spot with the ability to couple into an optical fiber.

Market Applications:

R&D labs applications:

  • Materials testing
  • UV-microscopy
  • Fluorescence spectroscopy

Advantages:

  • The brightness of the lamp is comparable to the brightness obtained from lasers making this invention a suitable low-cost replacement for expensive lasers in the current market.
  • Mercury free lamp with a multitude of wavelengths achievable by selecting different excimer gases.
  • Output wavelength line widths of 3 and 10 nanometers FWHM.
  • Lamp produces UV light through a narrow tube (~ 0.5 mm dia) providing a channeled and very bright light source with the ability to couple into an optical fiber.
  • Radiation from the lamp is in the form of a low divergence beam with extrapolated size less than 0.5mm.

Intellectual Property & Development Status:

Patent pending; the university holds related patents. A prototype high brightness lamp was built, tested, and used at an MIT lab. Output power of the lamp at 308nm wavelength was 4mW. Fiber optic coupling achieved with a brightness of about 100 mW/mm2 obtained through the fiber.