This paper describes the sensitivity of the HARP (High-gain Avalanche Rushing amorphous Photoconductor) tube. The sensitivity is 80 times that of a conventional tube e.g. SATICON or PLUMBICON), due to the use of a thick amorphous Se layer (6 μm), and a target voltage of 676 V. The tube, called Super-HARP, produces a high picture quality that is unattainable with conventional ultra-high-sensitivify image devices. It has a high resolution (maximum horizontal resolution of more than 800 TV lines), a low lag (decay lag in the third field of 1.6%), negligible additional noise, and no FPN (Fixed Pattern Noise) or blooming.
