Spectrometer Module With Nested Diffraction Units
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional spectroscopic modules face challenges in enhancing detection sensitivity for light across a wide wavelength range or different wavelength regions without increasing size, due to the limited efficiency of blazed diffraction gratings for specific wavelength regions.
Innovation Solution
The spectroscopic module incorporates a main unit with a first and second spectroscopic unit, photodetectors, and a reflection unit, where light is dispersed and reflected multiple times to enhance detection sensitivity across a wide wavelength range, while a light-absorbing layer and entrance portion are used to prevent size increase and minimize stray light.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If a blazed diffraction grating is used for dispersion, then the module size can be reduced, but the detection sensitivity for light in a wide wavelength range deteriorates
Solution Approach 1:
The dispersion function is segmented into multiple spectroscopic units (first spectroscopic unit with first diffraction grating, second spectroscopic unit with second diffraction grating), each optimized for different wavelength regions. This allows the system to maintain small size while achieving wide wavelength coverage through functional division.
Solution Approach 2:
The second spectroscopic unit serves multiple functions: it disperses second-order diffraction light from the first spectroscopic unit and also handles wavelength regions that the first spectroscopic unit cannot detect efficiently. This multi-functionality enables wide wavelength detection without proportionally increasing module size.
2Measurement precision
If multiple spectroscopic units are added to enhance detection sensitivity for wide wavelength range, then the detection sensitivity improves, but the module size increases
Solution Approach 1:
The second spectroscopic unit is positioned to utilize the optical path and space within the existing module structure. The spectroscopic units are nested in a compact arrangement where the second unit processes light that has already passed through the first unit, effectively nesting functions within the same spatial envelope.
Solution Approach 2:
The patent utilizes the spectral order dimension by capturing both first-order and second-order diffraction light from the first spectroscopic unit. The second spectroscopic unit processes the second-order light, effectively adding a dimensional approach to wavelength detection without requiring proportional increases in physical size.
3Object-affected harmful factors
If the light-absorbing layer and reflection unit are positioned between photodetectors, then stray light is inhibited, but the device complexity increases
Solution Approach 1:
The light-absorbing layer and reflection unit are merged into a single functional assembly positioned between the first and second photodetectors. This combined structure simultaneously performs light absorption and reflection functions, reducing the number of separate components while maintaining stray light inhibition effectiveness.
Solution Approach 2:
The light-absorbing layer acts as an intermediary element between the spectroscopic units and photodetectors, absorbing unwanted light before it reaches the detectors. The reflection unit then redirects useful light back toward the detection path, mediating between the dispersion system and detection system while filtering harmful stray light.
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 allows for accurate detection of light in a wide wavelength range or different wavelength regions without enlarging the module, effectively inhibiting stray light and improving sensitivity.
Implementation Method 1
a first spectroscopic unit, disposed on the other side of the main unit, for dispersing the light incident on the main unit
Implementation Method 2
a reflection unit for reflecting a second light having a second order diffraction light dispersed by the first spectroscopic unit
Implementation Method 3
a second spectroscopic unit, disposed on the other side of the main unit, for dispersing the second light reflected by the reflection unit
Implementation Method 4
a light-absorbing layer for absorbing the light
Data Source
AI summary
A spectroscopic module 1 is provided with a spectroscopic unit 8 and a photodetector 9 in addition to a spectroscopic unit 4 and a photodetector 5 and thus can enhance its detection sensitivity for light in a wide wavelength range or different wavelength regions of light. A light-transmitting hole 5b and a light-absorbing layer 12 are disposed between light detecting portions 5a, 9a, while a reflection unit 7 is provided so as to oppose the layer 12 (i.e., region R), whereby the size can be kept from becoming larger. Ambient light La is absorbed by the layer 12. Any part of the light La transmitted through the region R in the layer 12 is reflected to the region R by the unit 7 formed so as to oppose the region R, whereby stray light can be inhibited from being caused by the incidence of the light La.