Diffracting optical element, and optical system and optical apparatus having the same
AssigneeCanon Kabushiki Kaisha
InventorShuichi Kobayashi
Life of this patent
Estimating the term…
Abstract
A diffracting optical element has a structure that a plurality of layers having a periodic relief pattern varying in height in a period are laminated in proximity to or close contact with each other. The diffracting optical element includes two layers equal in the height of the relief pattern and opposite to each other in the direction in which the height of the relief pattern varies in a period, and another layer differing in the height of the relief pattern from the two layers. Materials forming the three layers differ in dispersion from one another.
Claims15
A diffracting optical element in which a plurality of layers having a periodic relief pattern varying in height in a period are laminated in proximity to or close contact with each other, comprising:
- two layers equal in the height of the relief pattern and opposite to each other in the direction in which the height of the relief pattern varies in a period;
- and
- another layer differing in the height of the relief pattern from said two layers;
- wherein materials forming said three layers differ in dispersion from one another.
A diffracting optical element in which a plurality of layers having a periodic relief pattern varying in height in a period are laminated in proximity to or close contact with each other, comprising:
- two layers equal in the height of the relief pattern and opposite to each other in the direction in which the height of the relief pattern varies in a period, materials forming said two layers differing in dispersion from each other;
- and
- another layer being the same as one of said two layers which is formed of a material smaller in dispersion in the direction in which the height of the relief pattern varies in a period, the material forming said another layer being greater in dispersion than both of the materials forming said two layers.
Dependencies are inferred from the claim text.