公开(公告)号：US20010015851A1

公开(公告)日：2001-08-23

申请号：US09801808

申请日：2001-03-09

Applicant: YEDA RESEARCH AND DEVELOPMENT CO., LTD.

Inventor： Yochay Danziger ,  Erez Hasman ,  Asher Friesem

IPC: G02B027/44 ,  G02B005/18

CPC classification number: G02B5/1876

Abstract: A multilevel diffractive optical element comprising a base and a plurality of phase zones having phase levels of a substantially identical height h, each phase zone being defined by a local modulation depth d and a local number of phase levels nullnulld/h, the local number of phase levels null per phase zone being a real number, an integer of which defines the number of complete levels in the phase zone, which complete levels have identical widths, and a fraction of which, in at least one phase zone, defines an incomplete level which is narrower than the complete levels, said local number of phase levels nullnullnull(x, y) varying among different phase zones so as to provide corresponding variation of said local modulation depth dnulld(x, y) whereby local diffraction efficiencies and consequently an overall diffraction efficiency of the optical element is arbitrarily controlled.

Abstract translation: 一种多级衍射光学元件，包括基极和具有基本相同高度h的相位电平的多个相位区域，每个相位区域由局部调制深度d和本地相位级数xgr = d / h定义， 本地相位级数xgr 每个相位区域是实数，其整数定义了相位区域中的完整水平的数量，其完整水平具有相同的宽度，并且其一部分在至少一个相位区域中限定较窄的不完整水平 表示本地数量的相位水平＆xgr; =＆xgr（x，y）在不同相位区域之间变化，以便提供所述局部调制深度d = d（x，y）的相应变化，由此局部衍射效率和 因此光学元件的总体衍射效率是任意控制的。