A short wavelength R-/spl theta/ scanning laser microscope and optical disc tester for the characterization of optical recording media

The design and applications of a novel, short wavelength, combined R-/spl theta/ scanning laser microscope (SLM) and optical disc tester that is used for the imaging of recorded bit structures and the characterization of optical recording media is described. The instrument is optimised for magneto-optical recording applications and provides images with sub-micron resolution. Imaging is achieved by focusing the light from an argon-ion laser (514 nm or 488 nm wavelength) to a diffraction limited spot on the surface of a rotating sample to generate the line scan, whilst moving the objective lens slowly in the radial direction to generate the frame scan.