Optical Measuring Device Light Guide Noise Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional optical measurement apparatuses face challenges in achieving a high signal-to-noise (S/N) ratio when the sample container is not completely housed, leading to difficulties in miniaturization due to the need for large light-shielding housings to accommodate noise light from external sources.
Innovation Solution
The optical measurement apparatus incorporates a light guide path with a transparent resin connected to a container cavity and a light absorbing unit that covers the periphery of the light guide path, ensuring a high S/N ratio by minimizing noise light entry, even if the sample container is not fully enclosed, using a ratio of the square root of the light entrance area to the distance from the entrance to the exit of 0.2 or less.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a light-shielding housing is used to cover the sample container and photodetector completely, then the S/N ratio is improved, but the device size increases and miniaturization becomes difficult
Solution Approach 1:
The patent extracts the light-shielding function from the housing structure and relocates it to a dedicated light-absorbing unit positioned adjacent to the light guide path. This separates the light-shielding function from the structural housing, allowing the housing to be minimized while maintaining effective noise light suppression through the specialized light-absorbing unit that selectively absorbs stray light without requiring complete enclosure of the sample container.
Solution Approach 2:
The patent introduces a light-absorbing unit as an intermediary element between the external environment and the light detection system. This intermediary selectively absorbs noise light (stray light from external sources) while allowing measurement light to pass through the light guide path to the photodetector. The light-absorbing unit acts as a mediator that filters harmful light without requiring complete housing enclosure, thus enabling miniaturization while maintaining high S/N ratio.
2Volume of moving object
If the sample container is not completely covered with a housing, then the device can be miniaturized, but noise light from external sources enters the photodetector and reduces S/N ratio
Solution Approach 1:
The patent applies local quality by positioning the light-absorbing unit specifically at the location where noise light enters the system (adjacent to the light guide path entrance), rather than providing uniform light-shielding coverage throughout the entire housing. This localized light-absorbing structure selectively suppresses noise light at its point of entry while allowing the device to remain miniaturized, as the light-absorbing unit is positioned precisely where it is most effective rather than requiring comprehensive enclosure.
3Measurement precision
If a light-absorbing unit is added to suppress noise light, then the S/N ratio is improved, but the device complexity increases
Solution Approach 1:
The patent merges the light-absorbing unit with the housing structure, integrating the noise suppression function into the existing structural framework rather than adding a completely separate complex subsystem. The light-absorbing unit is positioned within or adjacent to the housing, utilizing the same spatial envelope and material resources, thereby suppressing noise light while minimizing the increase in overall device complexity through functional integration rather than additive complexity.
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 design allows for compact optical measurement apparatuses with improved S/N ratios, reduced light scattering, and the elimination of the need for complex light-shielding mechanisms, enabling smaller device sizes and enhanced operability.
Implementation Method 1
a light guide path for guiding the light from the sample to the light detection unit
Implementation Method 2
a light absorbing unit for absorbing incident light
Implementation Method 3
via a transparent resin that transmits the light from the sample
Data Source
AI summary
An optical measuring device for measuring light emitted from a sample includes a container cavity for receiving a container in which the sample is enclosed; a light detection unit for detecting light from the sample; a light guide path for guiding the light from the sample to the light detection unit; and a light absorbing unit for absorbing incident light. An end of the light guide path to receive the incident light faces the container cavity, a light exit end of the light guide path faces the light detection unit, and the light absorbing unit covers the perimeter of the light guide path other than the light-receiving-end and the light exit end thereof.