We report on the fabrication and diffraction-limited characterization of parabolic focusing micromirrors. Sub–micron beam waists are measured for mirrors with 10-μm radius aperture and measured fixed focal lengths in the range from 24 μm to 36 μm. Optical characterization of the 3D intensity in the near–field produced when the device is illuminated with collimated light is performed using a modified confocal microscope. Results are compared directly with angular spectrum simulations, yielding strong agreement between experiment and theory, and identifying the competition between diffraction and focusing in the regime probed.
- confocal microscopy