Clearly Better Light on Fluorescence Microscopy

A high performance LED light source providing up to ten precise excitation wavelengths ideal for fluorescence microscopy has been launched by Carl Zeiss. Called Colibri, the computer-controllable unit will switch wavelengths in microseconds yet produces no heat or vibration, resulting in high contrast images rich in fine detail. The Colibri is ideally suited to replace metal halide light sources in all fluorescence microscopy applications, particularly in live cell imaging and other work with sensitive living specimens.

The intensity of the narrow-band LEDs (light emitting diodes) can be rapidly and accurately set for any wavelength, either from Zeiss' AxioVision software or directly from the manual controller. This allows users to balance the intensity of multiple excitation wavelengths and capture the result in a single image rather than taking multiple colour images and then attempting to balance the comparative intensities in software. The fine control of intensity also offers maximum protection for specimens and the narrow emission band produces a high signal-to-noise ratio, which is particularly significant for the detection of weak signals and fine details. The reproducibility of the illumination conditions is particularly important in medical diagnostics where documentation is made in accordance with GxP guidelines.
Rather than switching between wavelengths using filters, the different LEDs in Colibri are opto-electronically switched at extremely high speed an important asset in multi-wavelength and kinetic studies. Also, because no movement is involved, vibration is eliminated leading to accurate and highly resolved image capture.