Spectrometer Mask Plate for Stray Light Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Highly versatile monochromators face challenges in reducing stray light, as existing methods do not effectively block light that enters beyond the effective area of the diffraction grating, leading to adverse effects on measurement results.
Innovation Solution
A spectrometer configuration that includes an incidence part, a diffraction grating, a mask part, and a trap part, where the mask part reflects and blocks light that does not enter the effective area, and the trap part attenuates the reflected light, preventing it from reaching the diffraction grating and functioning as stray light.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the angular range of incident light flux is increased to improve sensitivity, then more light enters the diffraction grating, but light may enter beyond the effective area causing stray light
Solution Approach 1:
The patent extracts and isolates the problematic light rays that would otherwise enter beyond the effective area of the diffraction grating. By introducing a mask part that selectively blocks these specific light paths while allowing useful light to pass, the harmful stray light is separated from the useful incident light flux, enabling large angular ranges without contamination
Solution Approach 2:
The mask part serves as an intermediary element positioned between the incidence slit and the diffraction grating. It mediates the interaction between the broad angular light flux and the diffraction grating by selectively transmitting desired light while blocking light that would cause stray light, thus enabling the system to achieve both high sensitivity and low stray light
2Illumination intensity
If the F value is decreased to increase brightness, then the angular range increases, but light enters beyond the effective area of the diffraction grating
Solution Approach 1:
The mask part extracts and removes the harmful portion of the light flux that extends beyond the effective area. This allows the system to operate at low F values (high brightness) without the penalty of stray light contamination, as the mask selectively eliminates only the excess light rays that would cause problems
Solution Approach 2:
The mask part introduces local quality variation in the light path by creating different transmission properties at different positions. The central region allows light transmission while the peripheral regions (where stray light would originate) are blocked, enabling high brightness operation with controlled light distribution
3Measurement precision
If optical system adjustment is performed to optimize angular range, then measurement performance improves, but operational complexity increases
Solution Approach 1:
The mask part is pre-configured in a fixed position to automatically define the optimal angular range for light entry. This preliminary setup eliminates the need for users to perform complex real-time adjustments of the optical system, as the mask has already established the correct geometric constraints for optimal performance
Solution Approach 2:
The mask part enables the optical system to self-regulate the angular range of incident light. The fixed geometric configuration of the mask automatically limits the light flux to the appropriate angular range without requiring external control or adjustment mechanisms, simplifying operation while maintaining measurement precision
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 configuration effectively reduces stray light by blocking and attenuating light that exceeds the effective area of the diffraction grating, improving measurement accuracy and reducing operational complexity.
Implementation Method 1
the mask part blocks, by reflection, at least a part of the light that has passed through the incidence slit but does not enter the effective area
Implementation Method 2
The light having entered the housing reaches the diffraction grating while spreading, and is dispersed into light of different wavelengths by diffraction in the effective area (grating surface) of the diffraction grating
Implementation Method 3
The trap part has a trap space formed to attenuate the light reflected by the mask part
Data Source
AI summary
Provided are a spectrometer capable of more effectively reducing stray light and an incident light limiting member to be used for the spectrometer. At least a part of light not entering an effective area of a diffraction grating is blocked by being reflected by a mask plate provided between an incidence plate and the diffraction grating. Further, the light reflected by the mask plate is attenuated in a trap space. Thus, the light blocked by the mask plate does not reach the diffraction grating side and does not function as a stray light source, so that stray light can be more effectively reduced.