Diffractive Optics

I. Bragg-Fresnel zone plate designed for X-ray

Fig.1 A part of Bragg-Fresnel zone plate designed for X-ray of 8 keV (~1.5 A*) with focal distance 150 cm. The outmost zone is equal to 350 nm. The zone plate comprises patterned Au layer (220 nm in thickness) on Si substrate (by the courteously of A. Firsov, BESSY II ).

II. Design and creation of bifocal lens for Nomarski contrast

	Fig. 2a. Two-level phase zone plate designed for producing two focal spots
	Fig. 2b. Two-level phase zone plate created by one step e-beam lithography, working thickness about 0.6 um, PMMA
	Fig. 2c. Two observed focal spots separated with 10 um are coherent and have a phase shift of 180 deg (1.2 mm from hologram)