The invention discloses a weak X-
ray 3D (three-dimensional) imaging method. The used device is mainly composed of a weak X-
ray radiation source, a lens module, a detected object module, a detection array module, a
signal conditioning module, a host computer and a feedback adjusting module. The method comprises the following steps: step one, firstly emitting a beam from the weak X-
ray radiation source; step two, enabling the X-ray beam emitted from the step one to pass through the lens module to convert into a
parallel beam; step three, converting the
parallel beam into the
line source X-ray after passing through the detected object module; step four, converting the
line source X-ray into a current
signal after passing through the detection array module; step five, converting the current
signal into a
digital signal through the
signal conditioning module; step six, acquiring the
digital signal by the host computer; step seven, performing the feedback adjusting on the detected object module by the host computer; and step eight, outputting a 3D image through the host computer. The normal point X-ray source is converted into the line X-ray source through the method disclosed by the invention so that the detected
image signal is a linear signal, the operation is convenient and the efficiency is high.