Abstract
Photek are currently in a three year development program with CERN to produce a novel square PMT for the proposed TORCH detector which is aimed at the upgrade of the LHCb experiment. The PMT will be microchannel plate based for the inherent timing accuracy that this brings, and has three main novel features that need to be developed: it will be able to produce 5 C/cm2 of accumulated anode charge without any degradation in sensitivity. It will be able to detect simultaneous photons with an effective spatial resolution of 128 pixels in the ``y'' direction and 8 pixels in the ``x'' direction with a total working area of 53 × 53 mm. Finally it should be close packing on 2 opposing sides of a 60 mm wide detector envelope with an active area fill factor of 88% in the ``x'' direction.