Terahertz Ellipsometer Using Backward Wave Oscillator
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
There is a lack of commercially available ellipsometers or polarimeters capable of operating in the Terahertz frequency range, making it difficult to practice Terahertz ellipsometry at various locations, as existing systems rely on Synchrotrons which are not universally accessible.
Innovation Solution
A Terahertz ellipsometer or polarimeter system comprising a backward wave oscillator, rotatable polarizers, a stage for supporting a sample, and a Golay cell detector, with additional elements like concave parabolic mirrors and rotating retarders, enabling the generation and measurement of Terahertz electromagnetic radiation for characterizing samples.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If Synchrotrons are used as the electromagnetic radiation source, then Terahertz ellipsometry can be performed, but the system becomes inaccessible and unavailable at various locations
Solution Approach 1:
The patent creates a portable copy of the Terahertz ellipsometry system using a backward wave oscillator instead of requiring access to large Synchrotron facilities. This portable system replicates the essential measurement capability while being easily deployable at various locations.
Solution Approach 2:
The invention extracts the core measurement function from the massive Synchrotron infrastructure and isolates it into a compact, self-contained system using a backward wave oscillator, making the essential functionality portable and accessible.
2Ease of operation
If a portable system with backward wave oscillator is used, then accessibility is improved, but the system complexity increases
Solution Approach 1:
The system is divided into distinct functional modules: backward wave oscillator for THz generation, rotatable wire grid polarizers for polarization control, concave parabolic mirrors for beam focusing, and Golay cell detector for measurement. This modular segmentation enables portability while managing complexity through functional separation.
Solution Approach 2:
The patent employs rotatable wire grid polarizers that can be dynamically adjusted during measurement, allowing the system to adapt to different sample configurations and measurement requirements without requiring physical reconfiguration of the entire system.
3Adaptability or versatility
If rotatable polarizers and multiple mirrors are included, then measurement capability is enhanced, but the device complexity increases
Solution Approach 1:
The rotatable wire grid polarizers serve multiple functions: they act as both polarization state generators and analyzers, and their rotatability enables them to perform both fixed and variable angle measurements. The concave parabolic mirrors simultaneously focus the beam and enable the odd-bounce image rotation functionality.
Solution Approach 2:
The patent combines the odd-bounce image rotation system with the polarizer and analyzer functions into a unified optical path, where the same rotatable wire grid elements perform both polarization modulation and beam direction control, reducing the need for separate dedicated components.
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 provides a practical and accessible means to perform Terahertz ellipsometry, enabling the determination of physical and optical properties of samples in the Terahertz range, overcoming the limitations of existing systems by being compact and versatile.
Implementation Method 1
a backward wave oscillator; a frequency multiplier; a first concave parabolic mirror
Implementation Method 2
a first rotatable wire grid polarizer; a rotating wire grid polarizer; a second rotatable wire grid polarizer
Implementation Method 3
a first concave parabolic mirror; a second concave parabolic mirror; a third concave parabolic mirror; a fourth concave parabolic mirror
Implementation Method 4
a golay cell detector
Implementation Method 5
a rotating retarder comprising first, second, third and fourth elements
Data Source
AI summary
A terahertz ellipsometer, the basic preferred embodiment being a sequential system having a backward wave oscillator (BWO); a first rotatable polarizer that includes a wire grid (WGP1); a rotating polarizer that includes a wire grid (RWGP); a stage (STG) for supporting a sample (S); a rotating retarder (RRET) comprising first (RP), second (RM1), third (RM2) and fourth (RM3) elements; a second rotatable polarizer that includes a wire grid (WGP2); and a Golay cell detector (DET).