Abstract: Systems and methods for highly collimated and temporally variable X-ray beams. Disclosed herein is a system for producing a collimated X-ray beam, the system including one or more distributed electron sources configured to produce electron beams, one or more X-ray production targets configured to receive the electron beams and to generate X-ray beams at X-ray focal spots, X-ray optics configured to collect the X-ray beams from the X-ray focal spots, wherein the X-rays optics are configured to focus the X-ray beams to a single virtual focal spot, and an X-ray collimator configured to collimate the X-ray beams from the virtual focal spot to generate the collimated X-ray beam.