infrared radiation, ultraviolet, laser, multispectral, wavelengths, polarimetry, sensor, gamma ray, coronagraph, ultraviolet light, monocular, photometer, spectrometer, radiometer, spectroscopic, optical, laser beam, spectroscopy, bolometer, imager, spectrographic, photometry, infrared ray, spectro, galvanometer, photodetector, panchromatic, optics, interferometer, image intensifier, diffract, airglow, telescopes, diffraction, photomultipliers, pyrometers, detector, circular polarization, backscattering, ultrasonic, photoluminescence, fluorescence, lightwave, terahertz, electromagnetic, epsilon aurigae, eyepiece, spectral, spectra, galvo, photocells, plasmon, diffraction grating, ultraviolet lamp, collimated, photodiode, earthshine, illuminance, illuminator, waveband, thermopile, photometric, spectroscopic analysis, ionospheric, photoelectron, monochromator, unpolarized, retroreflector, collimator, scintillator, uncooled, emissivity, parabolic reflector, brightness, reflectance, ionisation, transmissive, illumination, electromagnetic spectrum, diffractive, absorbance, photons, reflector, neutron radiation, cherenkov radiation, binocular, emittance, gradiometer, photomultiplier, chemiluminescence, heliostat, refractor, collinear, attosecond, stereographic, grond, exoplanet, nebulas, eclipsing binary, deimos, arcsecond, ophthalmoscope, uv, microwave, receivers, sensors, spectrometers, transceivers, radiation, transmitting, detectors, leds, radars, thermal, transmitter, fio, lasers, phosphors, ir, ray, submillimeter, pulsed, monochromatic, wavelength, interferometric, scanning, xray, tunable, fluorescent, multichannel, photoacoustic, multiwavelength, photon

greenhouse emission, greenhouse gas, heat-seeking missile, heat lamp, herschel, infrared frequency, infrared lamp, infrared ray, infrared spectrum, infrared therapy, microwave, radio frequency, sidewinder, sir frederick william herschel, sir william herschel, stinger, thermograph, william herschel

actinic radiation, actinic ray, frequence, frequency, oftenness

infrared emission, infrared light, invisible, unseeable