Confocal microscopy is the latest state-of-art in the field of optical microscopy with wide ranging applications in the areas of surface microstructuring of metal and non-metal surfaces, finger print observations in forensic sciences, 3D volume rendering of biological specimen etc. A compact cpnfocal microscope layout in reflection mode is setup in our laboratory by utilizing He-Ne green laser, 50X infinity corrected plan objective as focusing optics and a single mode optical fiber as confocal detector. The object to be scanned is mounted on a precision XYZ translation stage with one micron resolution in XYZ directions. Electronic scanning software is developed for reconstruction of confocal images. The system also incorporates anti flex condition for blocking stray lights and thereby increasing contrast. The depth resolution of the setup is studied by scanning a mirror axially and lateral resolution is studied with the help of 1951 USAF test target. A 20μm × 10μm area copper-beryllium surface (SIM card) is scanned at focus and at a depth of 2μm away from focus. The reconstructed confocal image at focus clearly shows black patches of oxide formation on metal surface.
展开▼
