Cooled Intensifier

The Lambert Cooled Intensifier is a special camera attachment in which the complete Image Intensifier is cooled to reduce the noise of the photocathode. The noise reduction factor is at least 100, which means, that in combination with a low noise S20 photocathode, dark count rates below 0,5 cnts/sec/cm2!!! can be achieved. This makes it possible to acquire extremely faint phenomena which otherwise would have been masked by the noise of the intensifier. The Intensifier is a so-called hybrid tube. A hybrid tube is a two-stage image intensifier, which consists of a second generation tube as the first stage and a de-magnifying first generation tube as a second stage. Using the image intensifier as a de-magnifier instead of a lens offers a much more efficient coupling to the camera. With the fast shutter option, called gating, time resolved measurements are made possible.

The intensifier is cooled by means of a thermo-electric cooler (peltier cooler) The hot side of the peltier element is cooled with water. The intensifier is placed in an isolated housing and is thermally shielded from the outside by two isolating glass windows. A no-dew element prevents condensation of the input window.

A separate temperature control unit contains all the necessary electronics to provide power to the peltier elements and to control the temperature accurately. The unit also provides the power for the Image intensifiers.

Applications of the Cooled Intensifier are:

- astronomy
- photon imaging

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