Varifocal Lens Scanning Microscope Optical Axis Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Scanning microscopes face challenges in performing fast scans in the optical-axis direction due to mechanical movements, leading to long times for obtaining three-dimensional images, and varifocal lenses, while improving scan speed, introduce challenges in maintaining accurate image quality due to changes in focal length and aberrations.
Innovation Solution
A scanning microscope configuration that includes a varifocal lens for optical-axis direction scanning, a scanner for orthogonal directions, and a controller to generate and apply scan control data correcting deviations caused by the varifocal lens, ensuring accurate three-dimensional imaging by controlling both the scanner and varifocal lens.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If mechanical actuators are used to move the objective or stage for scanning in the optical-axis direction, then the scanning microscope can obtain three-dimensional images, but the scan speed is slow due to mechanical movement time and oscillation settling time
Solution Approach 1:
The patent replaces the mechanical actuator system with an optical system consisting of a varifocal lens and scanner. The varifocal lens changes focal length in response to scanner movements to achieve optical-axis scanning without mechanical movement of the objective or stage, thereby eliminating mechanical movement time and oscillation settling time.
Solution Approach 2:
The patent changes the focal length parameter of the varifocal lens dynamically during scanning. By varying the focal length in response to scanner position, the system achieves fast optical-axis scanning without mechanical movement, directly addressing the speed-time contradiction.
2Speed
If a varifocal lens is used for fast scanning in the optical-axis direction by changing focal length, then scan speed is improved, but scan position deviation and aberrations occur
Solution Approach 1:
The patent implements a feedback control system where the controller receives scanner position information and adjusts the varifocal lens focal length accordingly. This feedback mechanism compensates for scan position deviations and maintains accurate positioning despite the dynamic focal length changes.
Solution Approach 2:
The patent applies preliminary correction by pre-calculating or pre-programming the focal length adjustments needed to compensate for expected scan position deviations. The controller is configured to apply these corrections in advance or in real-time to maintain positioning accuracy.
3Speed
If a varifocal lens is used for fast scanning in the optical-axis direction by changing focal length, then scan speed is improved, but image quality deteriorates due to aberrations
Solution Approach 1:
The patent dynamically adjusts the focal length parameter of the varifocal lens while maintaining optimal image quality through controller coordination. The system changes focal length for scanning purposes while compensating for resulting aberrations to preserve image quality reliability.
Solution Approach 2:
The controller acts as an intermediary between the scanner and varifocal lens, coordinating their operations to maintain image quality. It adjusts focal length in response to scanner position while applying corrections for aberrations, thereby mediating between the need for fast scanning and the requirement for high image quality.
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
Enables fast and accurate three-dimensional imaging by correcting scan position deviations and aberrations, reducing the time required to obtain high-quality images compared to traditional mechanical scanning methods.
Implementation Method 1
Use of the varifocal lens allows a focal length to be rapidly changed by changing an applied current or voltage
Implementation Method 2
a scanning microscope is capable of performing a scan at a high frequency of hundreds to thousands Hertz using a galvanometer scanner or a resonance scanner
Implementation Method 3
a scan in an optical-axis direction (z-axis direction) is performed by moving the objective or a stage in the optical-axis direction typically using a piezoelectric transducer (hereinafter referred to as a piezo element)
Data Source
AI summary
A scanning microscope includes a laser configured to emit laser light, an objective configured to focus the laser light on an object, a scanner configured to scan the object in a direction orthogonal to an optical axis of the objective, a varifocal lens configured to scan the object in an optical-axis direction of the objective by changing a lens shape of the varifocal lens, a first relay lens configured to project the scanner onto the varifocal lens, a second relay lens configured to project a pupil of the objective onto the varifocal lens, a photodetector configured to detect fluorescence generated from the object upon the laser light being focused on the object by the objective, and a dichroic mirror configured to separate the fluorescence and the laser light emitted from the laser from each other. The varifocal lens is located between the objective and the scanner.