One embodiment provides an annular optical device, comprising: an annular meso-optic having a substantially triangular cross section and including an annulus centered about an axis of revolution; and a secondary optical structure substantially coaxial within the annulus of the annular meso-optic, wherein the secondary optical structure and the annular meso-optic are separated by a media comprising a media refractive index that is lower than a secondary optical structure refractive index, with the secondary optical structure being configured to hold a specimen to be radiated by impinging electromagnetic radiation directed into the secondary optical structure substantially along the axis of revolution, wherein re-directed radiation from the specimen is allowed into the annular meso-optic by the secondary optical structure if an angle of incidence of the re-directed radiation exceeds the angle of Total Internal Reflectance. Other embodiments are descried and claimed.