Seeing single photons

A photon detector based on the superconducting technology that can detect individual photons and identify their wavelength, is discussed. The heart of the detector is made out of a thin film aluminum on sapphire substrate. Photon detectors have a number of advantages over charged coupled devices (CCD) as CCD do not detect the wavelength of light. Highly sensitive single-photon detectors are reported to have a wide variety of uses, including astronomical observations, x-ray analysis, fluorescence microscopy, and telecommunication.