The performance of a tapered, monocapillary optic was compared to double-pinhole optics by measuring the intensity and widths of powder diffraction peaks generated using Cr Kα and Cu Kα X-rays (46 kV, 46 mA). A microdiffractometer and curved image-plate system was used to collect diffraction patterns displayed by an alumina intensity standard. A monocapillary optic with a 20 μm beam width (measured at half the maximum intensity, FWHM) was compared to collimating pinhole optics with two apertures: one with 30 μm diameter pinholes and another with 50 μm pinholes. The average, integrated intensity of the diffraction peaks in the patterns collected using the 20 μm monocapillary optic was 6 to 7 times greater than the average diffraction intensity obtained with the 50 μm pinhole collimator and 25 times greater than the intensity obtained with the 30 μm collimator. The average increase in the FWHM of the diffraction peaks in the patterns obtained with the monocapillary optic was ∼2 times greater than the pinhole collimators.
