Curved Sample Cell for Liquid Near-Field Microscopy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Scanning near-field optical microscopes face challenges in measuring samples in liquid environments due to spherical aberration, reduced signal-to-noise ratio (SNR), and measurement reproducibility issues caused by light interaction with the liquid interface, leading to inefficient detection of near-field light.
Innovation Solution
A scanning probe microscope design with a sample cell having curved surfaces to minimize aberration, combined with an optical lever detection system that stabilizes the laser light path through the liquid interface, enhancing the detection of near-field light and improving SNR and reproducibility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a plane surface sample cell is used to hold liquid sample, then the sample can be held for measurement, but spherical aberration occurs causing scattered light to cannot be focused and detection signal is reduced greatly
Solution Approach 1:
The patent applies spherical curvature to the sample cell surface to eliminate spherical aberration. Specifically, the sample cell is designed with a spherical surface that matches the curvature of the scattered light waves, allowing the light to focus properly on the detector. This converts the harmful spherical aberration caused by plane surfaces into a beneficial focusing effect, dramatically increasing the detection signal strength.
2Measurement precision
If scattered light penetrates the wall surface of plane surface sample cell, then detection is possible, but spherical aberration occurs so that scattered light cannot be focused on a point and photoelectric conversion efficiency is reduced
Solution Approach 1:
The sample cell is designed with a spherical surface that corresponds to the curvature radius of the scattered light. This spherical geometry allows the scattered light to converge properly at the detector position, eliminating the energy loss due to aberration and maximizing photoelectric conversion efficiency.
3Measurement precision
If most scattered light incident on the interface between atmosphere and liquid without penetrating wall surface, then total reflection occurs, but SN ratio and measurement reproducibility are reduced
Solution Approach 1:
The spherical surface of the sample cell is designed to match the curvature of scattered light waves, enabling proper focusing of light that would otherwise undergo total reflection at the atmosphere-liquid interface. This geometric design allows more scattered light to penetrate the wall surface and reach the detector, improving SN ratio and measurement reproducibility.
4Measurement precision
If laser light of optical lever detection system penetrates interface between atmosphere and liquid, then contact force can be read, but position varies due to liquid surface fluctuation generating signal fluctuation
Solution Approach 1:
The spherical surface design of the sample cell provides a consistent optical path for laser light penetration. The curved surface compensates for liquid surface fluctuations by maintaining a constant effective focal point, thereby stabilizing the laser light position and reducing signal fluctuation in contact force measurements.
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 design significantly increases the detection amount of near-field light and improves the SNR and measurement reproducibility of near-field light images, enabling high-resolution imaging of samples in liquid environments.
Implementation Method 1
laser light irradiation system to irradiate the measurement probe with laser light and generate near-field light between the measurement probe and the sample to be inspected in response to irradiation of the laser light
Implementation Method 2
the back of a cantilever in which the measurement probe is mounted is irradiated with laser light, so that contact force between the measurement probe and the sample is read from change in the position of reflected light thereof
Implementation Method 3
a detector to detect the near-field light which penetrates the sample cell
Data Source
AI summary
The purpose of the present invention is to increase the detection light amount of near-field light, which is generated in a liquid between a measurement probe and a sample-to-be-inspected, at the time of employing a near-field scanning microscope for measurement in a liquid, and to improve measurement reproducibility and the SN ratio of near-field light images. The present invention provides a scanning probe microscope comprising: a measurement probe that is relatively scanned over a sample-to-be-inspected; a laser beam irradiation system that irradiates the measurement probe with a laser beam; a sample cell that holds the sample-to-be-inspected and that transmits scattered light of near-field light generated between the measurement probe and the sample-to-be-inspected by the laser beam irradiation; and a detector that detects the scattered light that has passed through the sample cell.