Binary and multilevel diffractive lenses with submicrometer feature sizes

Zonal diffraction efficiencies and imaging of micro-Fresnel lenses

“…Coated Fresnel lenses with four and eight quantizations with the abovedescribed parameters have been used for a 1 : 6 imaging of a semiconductor laser in [16,17]. We compare our calculations with the measurement realized there.…”

“…The theoretical values for the height of the structure are 390 nm (four quantizations), and 455 nm (eight quantizations), while the measured values are 400 nm (four quantizations), and 480 nm (eight quantizations) [16]. Also production tolerances of the quantized levels as a mask mismatch may introduce further deviations.…”

“…The integral di raction e ciency of the Fresnel lenses with four and eight quantizations has been measured to be 64% and 72% respectively [16]. To compare these values with our calculations, we chose the local di raction e ciency results for the coated lens given in ®gure 12 for TE polarization and in ®gure 13 for TM polarization.…”

“…We would like to thank Dr H. Zarchizky (Siemens AG) for interesting discussions on e ciencies of silicon Fresnel lenses [16,17], and Dr M. Schmitz and Professor Y. Sheng for discussions on di ractive micro-optics.…”

“…For the other details see ®gure 9. section 3, the depth h of the structure is given by hˆ ¶= … n1 ¡ 1 †ˆ5 20 nm and the thickness hAR of the quarter-wave AR coating is then hARˆ162:5 nm. The lens has a focal length fˆ400 µ m and a diameter ¿ˆ600 µ m [15,16]. The calculation of the local (zonal) di raction e ciency over the zonal radius is performed for an uncoated and for a coated lens, assuming a constant height of the surface-relief pro®les.…”