Diffractive Optical Element with Asymmetric Lattice for Chromatic Aberration Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The optical system disclosed in prior art is sensitive to manufacturing errors due to a large refractive index difference in the diffractive optical element, leading to inadequate correction of chromatic aberration caused by prisms.
Innovation Solution
An optical system comprising a prism with non-rotationally-symmetric aspheric surfaces and a diffractive optical element with an asymmetric lattice structure, where the refractive index difference of the diffractive optical surface is between 0.53 and 0.005, optimizing the refractive power and diffraction efficiency to effectively correct chromatic aberration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a diffractive optical element with large refractive index difference is used to correct chromatic aberration, then the correction effect is improved, but the manufacturing error sensitivity increases
Solution Approach 1:
The patent applies parameter changes by optimizing the refractive index difference of the diffractive optical element to a specific range (0.005 < ΔNe < 0.53). This parameter optimization balances the chromatic aberration correction effectiveness with manufacturing error sensitivity, resolving the contradiction between correction performance and manufacturing precision.
2Reliability
If a free-shaped surface prism is used to correct eccentric aberration, then the optical system performance is improved, but chromatic aberration is introduced
Solution Approach 1:
The patent converts the harmful chromatic aberration introduced by the free-shaped surface prism into a correctable effect by introducing a diffractive optical element. The diffractive element's asymmetric lattice structure is specifically designed to compensate for the chromatic aberration, transforming the harmful factor into a beneficial correction mechanism.
Solution Approach 2:
The patent employs asymmetry by designing the diffractive optical element with an asymmetric lattice structure that matches the non-rotationally-symmetric aspheric surface of the prism. This asymmetric design enables the diffractive element to specifically correct the chromatic aberration induced by the eccentric prism, maintaining the overall optical performance while eliminating the harmful chromatic effect.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution provides a high-performance optical system with improved correction of chromatic aberration, reducing manufacturing error sensitivity and enhancing image quality by optimizing the refractive index difference and diffraction efficiency of the diffractive optical element.
Implementation Method 1
a diffractive optical element (13) having a lattice structure that is asymmetric about an optical axis (Ax)
Implementation Method 2
a prism (12) having a non-rotationally-symmetric aspheric surface for correcting eccentric aberration
Data Source
AI summary
This optical system (100) comprises a prism (12) and a diffractive optical element (13). The prism (12) has a non-rotationally-symmetric aspheric surface for correcting eccentric aberration, and the diffractive optical element (13) includes a diffractive optical surface (DM) having a lattice structure that is as about an optical axis (Ax) of the optical system (100). The following condition is satisfied where ΔNe represents the refractive index difference of the diffractive optical surface (DM) in relation to the e-line (546.074 nm).0.53>ΔNe>0.005 (1)