Anamorphic Projection Optics with Movable Cylindrical Lens Plates
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithographic projection systems face challenges in adjusting anamorphic magnification without excessive degradation of image properties, particularly in achieving precise alignment and magnification adjustments in multiple exposures.
Innovation Solution
A magnification adjustable projection system utilizing a pair of cylindrical lens plates, each with a movable configuration, and actuators to adjust distances between these plates, along with rotating corrector plates to correct for astigmatism, enabling continuous anamorphic magnification adjustments.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If magnification adjustment is achieved by adjusting projection lens or mask position, then alignment precision is improved, but image quality degradation occurs
Solution Approach 1:
The projection system is segmented into multiple optical components: a static projection lens and multiple movable cylindrical lens plates positioned at different locations (object space, image space, and intermediate positions). Each lens plate pair independently contributes to magnification adjustment in specific directions, allowing precise control without moving the entire projection lens or mask assembly.
Solution Approach 2:
The system employs dynamically adjustable cylindrical lens plates that can be independently positioned along the optical axis. The distance between each cylindrical lens plate and its corresponding reference plane is continuously variable, enabling real-time magnification adjustment while maintaining image quality through optimized optical path management.
2Adaptability or versatility
If anamorphic magnification is adjusted in clocking directions, then alignment flexibility is improved, but image property degradation increases
Solution Approach 1:
The system uses asymmetric cylindrical lens plate configurations with different orientations. The first pair of cylindrical lens plates has transverse axes oriented at a first angle, while the second pair has transverse axes oriented at a second angle (approximately 45° relative to the first). This asymmetric arrangement enables independent control of magnification in different clocking directions while correcting anamorphic distortion.
Solution Approach 2:
Each cylindrical lens plate pair serves multiple functions: (1) providing magnification power in specific directions, (2) enabling clocking adjustments for alignment flexibility, and (3) working in combination with other lens plates to correct anamorphic distortion. The rotating corrector plates further enhance universality by correcting various types of optical aberrations across different magnification settings.
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 system achieves precise anamorphic magnification adjustments across various clockings with minimal focal plane deviation and aberrations, maintaining image quality and efficiency in lithographic processes.
Implementation Method 1
a first pair of cylindrical lens plates located within the object or image space for contributing a first amount of magnification power to the imaging system
Implementation Method 2
the projection lens assembly further comprises a first rotating corrector plate located substantially parallel to a second rotating corrector plate, wherein the first and second rotating corrector plates each have a shaped surface and are movable relative to each other to correct for astigmatism
Data Source
AI summary
A magnification adjustable projection system includes an imaging system having a first pair of cylindrical lens plates located within an object or image space. The first pair of cylindrical lens plates includes a first cylindrical lens plate axially movable relative to a second cylindrical lens plate. A second pair of cylindrical lens plates is located within the object or image space in optical alignment with the first pair of cylindrical lens plates. The second pair of cylindrical lens plates includes a third cylindrical lens plate axially movable relative to a fourth cylindrical lens plates. First and second actuators adjusts distances between the first and second cylindrical lens plates and between the third and fourth cylindrical lens plates. The first and second pairs of cylindrical lens plates have first and second cylindrical transverse axes that are approximately 45° relative to each other.