Application of diffractive optical elements for controlling the light beam in ptychography

We designed two pieces of rotary diffractive optical elements (DOE) to control the incident light beam in ptychography. The incident light beam is shaped into the required complex amplitude as employed probes by using double DOEs. The high-quality probes are generated to illuminate on the different positions of the object, which leads to achieving superior ptychographical imaging by rotating DOEs. Consequently, mechanical movement of the specimen is avoided in the imaging process. The numerical experiments demonstrate the double-wheeling DOEs are effective for the ptychographical imaging. Further, the double discs containing several pairs of DOEs are designed for a larger field of view. As a result, the flexibility of ptychography may be improved by employing the rotary double DOEs. (C) 2013 Society of Photo-Optical Instrumentation Engineers (SPIE)