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Miniaturized radiance cameras measuring underwater multispectral radiances in all directions at high-radiometric accuracy (CE600) are presented. The camera design is described, as well as the main steps of its optical and radiometric characterization and calibration. The results show the excellent optical quality of the specifically designed fish-eye objective. They also show the low noise and excellent linearity of the complementary metal oxide semiconductor (CMOS) detector array that is used. Initial results obtained in various oceanic environments demonstrate the potential of this instrument to provide new measurements of the underwater radiance distribution from the sea surface to dimly lit layers at depth. Excellent agreement is obtained between nadir radiances measured with the camera and commercial radiometers. Comparison of the upwelling radiance distributions measured with the CE600 and those obtained with another radiance camera also shows a very close agreement. The CE600 measurements allow all apparent optical properties (AOPs) to be determined from integration of the radiance distributions and inherent optical properties (IOPs) to be determined from inversion of the AOPs. This possibility represents a significant advance for marine optics by tying all optical properties to the radiometric standard and avoiding the deployment of complex instrument packages to collect AOPs and IOPs simultaneously (except when it comes to partitioning IOPs into their component parts).

Near-field scanning optical microscopy (NSOM) offers high optical resolution beyond the diffraction limit for various applications in imaging, sensing, and lithography; however, for many applications the very low brightness of NSOM aperture probes is a major constraint. Here, we report a novel NSOM aperture probe that gives a 100× higher throughput and 40× increased damage threshold than conventional near-field aperture probes. These brighter probes facilitate near-field imaging of single molecules with apertures as small as 45 nm in diameter. We achieve this improvement by nanostructuring the probe and by employing a novel variant of extraordinary optical transmission, relying solely on a single aperture and a coupled waveguide. Comprehensive electromagnetic simulations show good agreement with the measured transmission spectra. Due to their significantly increased throughput and damage threshold, these resonant configuration probes provide an important step forward for near-field applications.