A method for reduction of parallax broadening in gas-based position sensitive detectors

A description is given of the principle and experimental verification of a new method which significantly reduces broadening of the position response, due to parallax, for radiation incident on a detector at finite angles of incidence. The technique, which can be implemented in gas-based position-sensitive detectors with planar geometry, substantially improves position resolution for scattering experiments using X-rays and neutrons, and will permit larger angular coverage than has previously been possible. An improvement of nearly a factor four in rms position resolution is predicted, which is confirmed by measurements using a gas proportional X-ray detector with delay-line position encoding