Optical detectors for infrared, sub-millimeter and high energy radiation

An essentially planar detector of electromagnetic or other radiation, said detector including an essentially planar absorber of said radiation having dimensions, area and thermal mass not substantially greater than minimally needed for the capture of a desired fraction of the intensity of said radiation incident on the detector, and at least one temperature probe attached to or incorporated into said absorber and comprised of a photoluminescent material so characterized that, when exposed to said radiation and illuminated with luminescence excitation light of suitable wavelength or wavelengths and pre-selected intensity, it absorbs at least a fraction of the intensity of said excitation light, thereby generating a luminescence light separable from the illuminating light, at least part of the intensity of which is emitted from the probe at visible or near infrared wavelengths including λf different from those of said excitation light, the intensity and/or spectral distribution of said luminescence light being indicative of the probe temperature, the detector being characterized by undergoing a temperature rise upon the absorption of said radiation and further so characterized that its thermal mass at its operating temperature is not significantly greater than 1.1 times the mass of said absorber alone.