Optical Encoder Segmentation for Thermal Error Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optical encoders are large, prone to measurement errors due to thermal expansion, and have slow computational speeds, making them unsuitable for precise and fast position measurement in various applications.
Innovation Solution
A location system comprising a digital image sensor and a programmable logic device (PLD), such as a field programmable gate array (FPGA), that captures images of a target pattern, generates image vectors from pixel values, and determines absolute positions in two dimensions, allowing for simultaneous processing and reducing size and thermal expansion errors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If known optical encoding architectures are used, then position measurement can be achieved, but the encoder size becomes large causing thermal expansion errors and limiting implementation settings
Solution Approach 1:
The patent segments the optical encoder into two separate components: a compact optical sensor module and a separate processor. This segmentation allows the optical sensor to be small and precise while the processor handles computations remotely, eliminating thermal expansion errors in the measurement path and enabling implementation in settings with limited space.
2Measurement precision
If known optical encoders are used, then position measurement is possible, but computational speed is slow reducing processing speed of measurement data
Solution Approach 1:
The patent introduces a processor as an intermediary component that is spatially separated from the optical sensor. This intermediary handles all computational tasks remotely, allowing the optical sensor to focus solely on capturing position data at high speeds without computational bottlenecks, thereby achieving both precision and high productivity.
3Reliability
If housing is added to prevent contamination, then protection from ambient elements is improved, but encoder size increases further
Solution Approach 1:
The patent extracts the computational functions from the optical sensor module and places them in a separate processor. This extraction allows the optical sensor to be enclosed in a protective housing for contamination prevention while the housing size is minimized because the computational components are located externally in the separate processor, not within the sensor enclosure.
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 precise, fast, and compact position measurement with reduced thermal expansion errors, enabling its use in diverse applications where size and speed are critical.
Implementation Method 1
light from a light source is incident on a target pattern on the object. An optical sensor captures an image of the target pattern
Data Source
AI summary
A location system and a location system on a chip (LCoS) and method are described.