The Leica DMLA microscope with a CCD camera



  • Leica DMLA
  • C-mount/F-mount/0.5x TV optics 0.5x for CCD camera
  • 10x eyepiece, binocular phototube with photoprism for beam separation
  • motorised, electronically steerable 6x objective revolver
  • air objectives 5x/0.15, 10x/0.30, 20x/0.70, 40x/0.75
  • oil immersion objectives 63x/1.32, 100x/1.35
  • motorised, electronically steerable focus drive, resolution 0.015µm
  • motorised, electronically steerable x/y stage, resolution 0.3µm
  • external control gear, PC interface RS 232C
  • comprehensive software developer’s kit (SDK)
  • ergonomic x/y/z manual control element


  • JAI CV-M90
  • 3-CCD, 1/3″
  • resolution 752×582 pixels
  • pixel size 6.50µm x 6.25µm (at PAL)
  • shutter speeds 1/60sec – 1/10000sec
  • electronically steerable (e.g. shutter speed , RGB gain)

PC system:

  • Intel Pentium architecture
  • RAID drives
  • dual head graphics card for simultaneous display of the live image on a second screen
  • frame grabber
  • data exchange with database and RAID image archiving system over 1 GBit network

The microscopy hardware employed at the Institute of Imaging & Computer Vision offers all the prerequisites for the development of a forward-looking digital microscopy workstation. The Leica DMLA is equipped with corrected objectives for high imgage contrast and a sharp, low-distortion, chromatically corrected imaging. The light source, connected via a stabilized power source, facilitates a constant, low fluctuation illumination of the field of view with Köhler illumination. A 3-chip CCD camera with large detector elements ensures low losses during image acquisition.

All components have been assembled with a particular focus on automation. For example, the Leica DMLA offers functionality for fast, reproducible positioning of the X/Y stage, adjustment of the focal plane (autofocus, with problem-adapted algorithms from the Institute of Imaging & Computer Vision), and lens changes for exposures with changing field of view. Camera parameters, such as channel-dependent gain or shutter speed, can also be controlled electronically. This enables, for instance, automatic white balancing or high dynamic range imaging (HDR).

Highly automated image analysis systems of the future will also require intuitive and transparent user interfaces. The external control element of the microscope, which allows X/Y stage position, focus and lens selection to be changed with one hand, and the simultaneous display of the live camera image and an application on two screens provide the basis for an ergonomic and efficient workflow.

One application example for the microscope workstation is the Multimodal Cell Analysis (MMCA), in which a cell preparation from cytopathological cancer diagnostics is first stained in one of several different stains. Cell images are then captured  and analyzed by computer, whereby the X/Y stage position per image is stored in a database. If the first staining does not yet allow an unambiguous diagnosis, the preparation is re-stained (several times if necessary) so that other cell features become visible, and the recording and analysis process is repeated. The trick is that the cells retain their position during the re-staining process, and with the help of the previously stored X/Y stage position, images of identical cells are obtained. Thus, for each cell, a progressively increasing vector of diagnostic measurements is obtained, synergistically combining the analyses.