OCT Scanner Beam Deflection Position Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optical systems face challenges in achieving precise and fast beam deflection with minimal moving mass, particularly in high-precision applications like coordinate measuring machines and OCT scanning, where accurate positional control and high dynamic performance are required.
Innovation Solution
An optical system with a beam deflection unit that utilizes an optical component with a back reflection mechanism, where the longitudinal position of the back reflection is used to determine the lateral or angular deflection, allowing for precise control and high-speed operation without significant mechanical changes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If moving deflection mirrors are used for beam scanning, then lateral scanning capability is achieved, but position control accuracy and feedback precision deteriorate
Solution Approach 1:
An optical component is introduced as an intermediary element in the beam path. This component has a laterally variable longitudinal back reflection position that serves as a mediator between the deflection unit and the OCT measurement, enabling indirect but precise position detection without directly measuring the deflection mirror itself
Solution Approach 2:
The mechanical position measurement of the deflection mirror is replaced by an optical measurement system. Instead of mechanically sensing the mirror position, the system uses OCT to measure the longitudinal back reflection position of an optical component, substituting mechanical measurement with optical interferometry for higher precision
2Volume of moving object
If MEMS mirrors are used for miniaturization, then device size is reduced, but position accuracy and reliability deteriorate
Solution Approach 1:
The optical component acts as an intermediary that translates the small, hard-to-measure deflections of miniaturized MEMS mirrors into a measurable longitudinal back reflection position change. This mediator amplifies the measurement signal while preserving the miniaturized structure
Solution Approach 2:
The measurement is shifted from the lateral dimension (where MEMS deflections are small and difficult to measure) to the longitudinal dimension (where back reflection position changes are amplified and easily measurable by OCT). This dimensional transformation enables high-precision measurement of miniaturized components
3Productivity
If high-speed beam deflection is achieved, then scanning speed is improved, but position feedback accuracy deteriorates
Solution Approach 1:
The position feedback system replaces mechanical position sensors with optical coherence tomography measurement. This substitution enables high-speed measurement because OCT can rapidly measure the longitudinal back reflection position without the mechanical inertia and bandwidth limitations of traditional position sensors
Solution Approach 2:
The optical component itself provides the measurement signal through its back reflection property. The component being measured (the optical path position) automatically generates the measurement signal (back reflection), eliminating the need for separate measurement devices that could limit speed
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 precise and rapid beam deflection with accurate positional feedback, enhancing the performance of optical coherence tomography (OCT) systems and coordinate measuring machines by using the OCT measurement to determine the deflection unit's position, thereby improving scanning accuracy and speed.
Implementation Method 1
a beam deflection unit for lateral deflection, in particular positional and/or angular deflection, of a beam path of the OCT measuring device
Implementation Method 2
an optical component in the beam path, which is designed such that, depending on the lateral position of the deflected beam path on the optical component, a back reflection of the optical component is designed differently in its longitudinal position along the beam path
Implementation Method 3
a non-contact measurement is generally carried out using interferograms of a measuring beam directed axially into the object depth with a superimposed reference steel, in the sense of white light or short coherence interferometry
Data Source
Figure 1a~1c
Figure 2a~2c
Figure 3~4b
AI summary
The invention relates to an optical system (1), in particular an OCT scanner, comprising an optical coherence tomography (OCT) measuring device and a beam deflection unit for lateral positional and/or angular deflection of a beam path of the OCT measuring device. According to the invention, an optical component is located in the beam path, which is configured such that, depending on the lateral position of the deflected beam path on the optical component, a back reflection of the optical component is configured differently in its longitudinal position along the beam path. The optical system has an evaluation unit which is configured such that a value of the lateral positional and/or angular deflection of the beam deflection unit can be determined based on a longitudinal position of the back reflection on the optical component determined by the OCT measuring device.