Liquid Immersion Objective Chromatic Aberration Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional liquid immersion objectives for microscopes face challenges in correcting chromatic aberration across various immersion liquids, especially when a large numerical aperture and long working distance are required, as existing correction methods primarily address spherical aberration and fail to adequately compensate for chromatic aberration changes.
Innovation Solution
Incorporating a plurality of planar plates with different thicknesses, made of the same material, between the objective lens and the immersion liquid, which are selected based on the Abbe number of the immersion liquid to correct chromatic aberration, ensuring proper optical alignment and minimizing chromatic aberration effects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a correction ring is used to move a part of the correction lens group along the optical axis to compensate for spherical aberration, then spherical aberration is corrected, but chromatic aberration cannot be changed to any significant extent
Solution Approach 1:
The correction lens group is divided into a first lens group and a second lens group. The first lens group remains fixed while the second lens group is movable along the optical axis. This segmentation allows independent control of spherical and chromatic aberration corrections, resolving the limitation where previous single-group movement could not adequately address chromatic aberration.
Solution Approach 2:
The second lens group is designed to be movable along the optical axis, enabling dynamic adjustment of the optical system. This dynamic configuration allows the lens positions to be changed based on the specific immersion liquid being used, facilitating effective chromatic aberration correction while maintaining spherical aberration compensation.
2Length of stationary object
If the thickness of the cover glass is increased to achieve a long working distance, then the working distance is extended, but chromatic aberration changes due to different immersion liquids become more significant
Solution Approach 1:
A correction lens group is introduced as an intermediary optical element between the cover glass and the sample. This correction lens group specifically addresses chromatic aberration caused by different immersion liquids, allowing the cover glass thickness to be increased for longer working distance without compromising optical quality.
Solution Approach 2:
The optical system parameters are adjusted by changing the position of the movable second lens group along the optical axis. This parameter change enables the system to adapt to different immersion liquids and their associated chromatic aberrations, maintaining high measurement precision even with increased cover glass thickness for extended working distance.
3Measurement precision
If a liquid immersion objective with large numerical aperture and large working distance is designed, then both high resolution and long working distance are achieved, but compensation for chromatic aberration across various immersion liquids becomes difficult
Solution Approach 1:
The movable second lens group provides dynamic adjustability that enables the objective to adapt to different immersion liquids. By changing the position of the second lens group, the system can compensate for chromatic aberration variations across multiple immersion liquids, maintaining high resolution and versatility simultaneously.
Solution Approach 2:
The correction lens group with its divided structure serves multiple functions: it corrects spherical aberration through the fixed first lens group and chromatic aberration through the movable second lens group. This multi-functional design makes the objective universally adaptable to various immersion liquids while maintaining large numerical aperture and working distance.
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
This solution allows for accurate and clear observation of biological samples by effectively correcting chromatic aberration for different immersion liquids, enabling a wide range of applications with a long working distance and high numerical aperture without requiring complex lens movement mechanisms.
Implementation Method 1
due to the differences in the dispersion of the different immersion liquids (or the differences in the Abbe numbers of the different immersion liquids), and the resulting changes in the chromatic aberration
Implementation Method 2
differences in the dispersion of the different immersion liquids
Implementation Method 3
an objective lens (3) having a prescribed optical power
Data Source
AI summary
Provided is a liquid immersion objective including an objective lens having a prescribed optical power, and a plurality of planar plates having substantially no optical power and having different thicknesses, and configured to be placed between the objective lens and immersion liquid deposited on a sample to be observed, the planar plates being made of a substantially same material, wherein the planar plates being selected according to a property of the immersion liquid.