Chromatic Optical Sensor Layout for Precise Surface Distance Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optical displacement sensors face challenges in achieving high accuracy and reliability while maintaining a straightforward design and small size, often compromising on complexity and size to enhance measurement performance.
Innovation Solution
An optical sensor apparatus with an illumination assembly, beam splitter, first and second optical assemblies, and a light sensor assembly that uses wavelength dispersion and focusing to determine surface characteristics, allowing for precise measurements without increasing size or complexity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional optical designs are used to improve measurement accuracy and reliability, then measurement precision improves, but device size and complexity increase
Solution Approach 1:
The optical system is segmented into distinct functional assemblies: an illumination assembly with multiple light sources emitting at different wavelengths, a first optical assembly for longitudinal dispersion, a second optical assembly for lateral dispersion, and a light sensor assembly. This segmentation allows each component to be optimized independently for its specific function, achieving high measurement accuracy without requiring a monolithic complex design.
Solution Approach 2:
The patent introduces longitudinal dispersion (first optical assembly) and lateral dispersion (second optical assembly) as additional dimensional separations in the optical path. By dispersing light in both longitudinal and lateral dimensions, the system creates well-separated spectral patterns on the sensor plane, enabling high-accuracy wavelength-based distance measurements while maintaining a compact overall design through efficient spatial utilization.
2Measurement precision
If conventional optical designs are used to improve measurement accuracy and reliability, then measurement precision improves, but device size increases
Solution Approach 1:
The optical assemblies are arranged in a nested or cascaded configuration where the illumination assembly feeds into the first optical assembly, which feeds into the second optical assembly, and finally to the light sensor assembly. This nesting allows the system to achieve multiple optical functions (illumination, longitudinal dispersion, lateral dispersion, detection) in a compact sequence, minimizing the overall device volume while maintaining measurement accuracy.
Solution Approach 2:
By utilizing both longitudinal and lateral dispersion dimensions, the patent efficiently packs the optical functionality into a compact volume. The double dispersion approach creates separated spectral patterns that fit within a small sensor plane, allowing high-accuracy measurements without requiring a large optical path length or device footprint.
3Adaptability or versatility
If multiple light sources with different wavelengths are used to extend measurement range, then measurement range increases, but device complexity increases
Solution Approach 1:
The patent employs multiple light sources emitting at different wavelengths within a predefined range, where each wavelength can be focused at different distances by the longitudinally dispersing first optical assembly. This multi-wavelength approach allows a single optical system to measure distances across an extended range by simply changing which wavelength is in focus, providing versatility without requiring multiple separate optical systems for different distance ranges.
Solution Approach 2:
The system changes the wavelength parameter of the emitted light to adjust the measurement range. By having light sources cover a predefined wavelength range and using the wavelength-dependent focusing property of the first optical assembly, the measurement range is extended simply by utilizing different wavelengths, without adding mechanical moving parts or complex switching mechanisms.
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 apparatus enables accurate and reliable measurements of surface characteristics with a compact design, utilizing chromatic dispersion to distinguish focused and unfocused light intensities for precise distance and optical property determination.
Implementation Method 1
a first optical assembly arranged to longitudinally disperse the light emitted from the illumination assembly such that light across the predefined range of wavelengths from each of the one or more light emitting area patterns is focused at a respective range of focus distances
Implementation Method 2
a second optical assembly arranged to receive the folded light across the predefined range of wavelengths, to laterally disperse the received light across the predefined range of wavelengths
Implementation Method 3
a beam splitter arranged to transmit the light emitted from the illumination assembly towards the first optical assembly and to fold the light reflected from the surface of the object received through the first optical assembly
Implementation Method 4
an illumination assembly comprising one or more light sources arranged to emit light towards the measurement range through a light-collecting optical assembly, wherein the emitted light covers a predefined range of wavelengths
Data Source
AI summary
According to an example embodiment, an optical sensor apparatus (110) for determining at least one characteristic of a surface of an object (180) positioned within a measurement range is provided, the sensor apparatus (100) comprising: an illumination assembly (120) comprising one or more light sources (121, 121-k) arranged to emit light towards the measurement range through a light-collecting optical assembly, wherein the emitted light covers a predefined range of wavelengths and wherein the one or more light sources are arranged to form respective one or more light emitting area patterns of predefined lateral shape; a first optical assembly (140) arranged to longitudinally disperse the light emitted from the illumination assembly (120) such that light across the predefined range of wavelengths in each of the one or more light emitting area patterns is focused at a respective range of focus distances that constitutes a corresponding sub-range of candidate distances within the measurement range; a beam splitter (130) arranged to transmit the light emitted from the illumination assembly (120) towards the first optical assembly (140) and to fold the light reflected from the surface of the object (180) received through the first optical assembly (140); a second optical assembly (150) arranged to receive the folded light across the predefined range of wavelengths, to laterally disperse the received light across the predefined range of wavelengths and to focus the light across the predefined range of wavelengths at a predefined distance; a light sensor assembly (160) having a sensor plane arranged at the predefined distance to receive the laterally dispersed light across the predefined range of wavelengths such that the light originating from the one or more light emitting area patterns is received at respective one or more corresponding sub-ranges of positions along an axis (y′) on the sensor plane; and a detector assembly (170) arranged to determine the at least one characteristic of said surface of said object (180) based on the laterally dispersed light received across said one or more sub-ranges of positions along said axis (y′) on the sensor plane.