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A position sensitive one‐dimensional x‐ray detector with a large dynamic range (≳214:1) for high photon fluxes with fast image recording sequence (300 ms per frame) has been developed for transvenous coronary angiography with synchrotron radiation. A position resolution of 1 LP/mm and a detection quantum efficiency (DQE) of at least 58% (for 11 000 photons per pixel) has been achieved for 33 keV photons in a Xe‐CO2 gas mixture at 20 bars. The use of Kr‐CO2 as conversion gas provides a better contrast of the weak iodine signal than Xe‐CO2 or Si, respectively, for a fraction of 2% of the second harmonics of the synchrotron beam used.

High photon fluxes are crucial in dichromatic digital subtraction angiography with line scan systems to allow for adequate image quality. To obtain images wide enough and with sufficient vertical resolution, each of the two beams used has to be at least 100 mm wide but not more than 0.5 mm high at the patient’s heart with the beam energies bracketing the iodine‐K edge at 33.17 keV. A new monochromator in Laue transmission geometry has been developed, successfully tested at beamline ID11 of the European Synchrotron Radiation Facility (ESRF) and is now in use at the angiography wiggler beamline W2 at HASYLAB. The monochromator consists of two almost identical goniometer heads which are independently controlled. Within each head a bent silicon single crystal extracts a quasimonochromatic beam and focuses it vertically to the patient thus also increasing intensity compared to an unbent crystal. With a storage ring current of 50 mA the new monochromator provides 0.8×1011 photons/mm2/s in front of the patient w...