In-situ X-ray diffraction system using sources and detectors at fixed angular positions

An x-ray diffraction apparatus for measuring a known characteristic of a sample of a material in an in-situ state, comprising:

• an x-ray source for emitting substantially divergent x-ray radiation;
• a collimating optic disposed with respect to the fixed source for producing a substantially parallel beam of x-ray radiation by receiving and redirecting the divergent paths of the divergent x-ray radiation toward the sample;
• and
• first and second point x-ray detectors for collecting radiation diffracted from the sample, wherein the first x-ray detector is fixed in position to measure a diffraction peak determined according to the a-priori knowledge, and wherein the second x-ray detector is fixed in position to measure off the diffraction peak determined according to the a-priori knowledge;
• wherein the source and detectors are fixed, during operation thereof, in positions relative to each other and in at least one dimension relative to the sample according to a-priori knowledge about the known characteristic of the sample.