Grating patterns and method for determination of azimuthal and radial aberration
AssigneesInfineon Technologies AG, International Business Machines Corporation
InventorsGerhard Kunkel, Shahid Butt, Joseph Kirk
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Abstract
Methods and reticles for evaluating lenses are disclosed. In one instance, a reticle which permits light to pass therethrough is provided which includes a first surface with a grating profile formed thereon. The grating profile includes a plurality of grouped stepped portions. Each group of the stepped portions includes a first step which prevents light from propagating therethrough, a second step which propagates light therethrough and a third step which propagates light therethrough at an angle 60 degrees out of phase with the light propagated through the second step.
Claims35
An apparatus for evaluating a lens, comprising:
- a reticle which permits light to pass therethrough including a first surface;
- a grating profile formed on the first surface, the grating profile including a plurality of grouped stepped portions;
- each group of the stepped portions including:
- a first step which prevents light from propagating therethrough;
- a second step which propagates light therethrough;
- and
- a third step which propagates light therethrough at an angle 60 degrees out of phase with the light propagated through the second step.
An apparatus for evaluating a lens, comprising:
- a reticle which permits light to pass therethrough including a first surface;
- a grating profile formed on the first surface, the grating profile including a plurality of grouped stepped portions;
- each group of the stepped portions including:
- a first step which propagates light therethrough at a first phase angle;
- a second step which propagates light therethrough at an angle 90 degrees out of phase with the first phase angle;
- and
- a third step which propagates light therethrough at an angle 180 degrees out of phase with the first phase angle.
A method for evaluation of a lens for azimuthal aberrations, comprising the steps of:
- providing a diffractcd reticle image by propagating light through the reticle, the reticle including a grating profile including a plurality of grouped stepped portions, each group of stepped portions including:
- a first step which prevents light from propagating therethrough;
- a second step which propagates light therethrough;
- and
- a third step which propagates light therethrough at an angle 60 degrees out of phase with the light propagated through the second step;
- focusing the diffracted reticle image to determine a focus setting for a maximum amplitude of a first diffraction for a plurality of reticle angles;
- plotting the focus settings versus the rericle angles to obtain a plot;
- and
- matching the plot against a library of plots or simulations to determine azimuthal aberrations for evaluating the lens.
A method for evaluation of a lens for azimuthal aberrations, comprising the steps of:
- providing a diffracted reticle image by propagating light through the reticle, the reticle including a grating profile including a plurality of grouped stepped portions, each group of stepped portions including:
- a first step which prevents light from propagating therethrough;
- a second step which propagates light therethrough;
- and
- a third step which propagates light therethrough at an angle 60 degrees out of phase with the light propagated through the second step;
- recording an intensity profile at a constant focus setting for the diffracted reticle image to provide a plot of intensity as a function of position in the diffracted reticle image;
- and
- matching the plot against a library of plots or simulations to determine azimuthal aberrations for evaluating the lens.
A method for evaluation a lens for azimuthal aberrations, comprising the steps of:
- providing a diffracted reticle image by propagating light through the reticle, the reticle including a grating profile including a plurality of grouped stepped portions, each group of stepped portions including:
- a first step which propagates light therethrough at a first phase angle,
- a second step which propagates light therethrough at an angle 90 degrees out of phase with the first phase angle, and
- a third step which propagates light therethrough at an angle 180 degrees out of phase with the first phase angle;
- focusing the diffracted reticle image to determine a focus setting for a maximum amplitude of a first diffraction for a plurality of reticle angles;
- plotting the focus settings versus the reticle angles to obtain a plot;
- and
- matching the plot against a library of plots or simulations to determine azimuthal aberrations for evaluating the lens.
A method for evaluation a lens for azimuthal aberrations, comprising the steps of:
- providing a diffracted reticle image by propagating light through the reticle, the reticle including a grating profile including a plurality of grouped stepped portions, each group of stepped portions including:
- a first step which propagates light therethrough at a first phase angle,
- a second step which propagates light therethrough at an angle 90 degrees out of phase with the first phase angle, and
- a third step which propagates light therethrough at an angle 180 degrees out of phase with the first phase angle;
- recording an intensity profile at a constant focus setting for the diffracted reticle image to provide a plot of intensity as a function of position in the diffracted reticle image;
- and
- matching the plot against a library of plots or simulations to determine azimuthal aberrations for evaluating the lens.
Dependencies are inferred from the claim text.