Low Pass metallic mesh interference filters for operation in the 165 GHz to 880 GHz region

Low Pass metallic mesh interference filters have been designed and constructed for operation in the region 340 m (880 GHz) to 1.8 mm (165 GHz). These filters have been shown to have excellent edge characteristics and good rejection regions. The results show that the mesh filter can be effectively used in both millimetre and submillimetre regions.Part of this work was performed while this author was at Heriot-Watt University, Edinburgh, U.K.     

The influence of background power on the performance of an ideal bolometer

The effects of radiant power loading on the performance of an ideal bolometer are analysed. The operation of the bolometer is characterized in terms of dimensionless parameters which correspond to the temperature sensitivity of the thermometric material, the electrical bias point and the amount of optical power loading. Expressions are derived for the zero frequency NEP and responsivity. Examples are given for the case of a bolometer cooled to 100 mK and used for ground-based astronomical photometry at submillimetre wavelengths.     

Modelled V-I Performance of A 3HE Composite Bolometer Detector

The V-I characteristics of a ³He-cooled, composite bolometer detector designed for submillimetre astronomy are modelled. The modelling yields detector parameters that cannot be measured directly. The system NEP predicted from theoretical V-I equations is found to agree with the measured noise values. The calculated dynamic thermal conductance and the electrical responsivity are found to deviate from the standard model at low temperatures.