Photoelectric Encoder Miniaturization via 3D Optical Path
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional photoelectric encoders with a two-dimensional structure for detecting diffracted light beams result in increased size, hindering miniaturization.
Innovation Solution
A photoelectric encoder with a three-dimensional structure is achieved by using a mirror to reflect diffracted light beams in a direction parallel to the scale plane, incorporating a non-polarization beam splitter, detectors with polarizing plates, and half wave plates to maintain optical properties and improve measurement accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a two-dimensional structure is used to detect diffracted light beams, then the detection function is achieved, but the size of the photoelectric encoder is increased
Solution Approach 1:
The patent transitions from a two-dimensional optical path arrangement to a three-dimensional structure by introducing a mirror that reflects diffracted light beams in a direction parallel to the scale plane. This dimensional change allows the optical components to be arranged in three-dimensional space rather than requiring a larger two-dimensional area, thereby achieving miniaturization while maintaining the detection function
Solution Approach 2:
The patent combines multiple optical functions into a compact three-dimensional arrangement where the mirror, non-polarization beam splitter, and detectors with polarizing plates work together in an integrated optical path. This merging of optical elements in three-dimensional space reduces the overall device size compared to traditional two-dimensional layouts
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 miniaturization of the photoelectric encoder is realized while maintaining high measurement accuracy and optical properties, enhancing the device's compactness without compromising performance.
Implementation Method 1
a scale having a reflective diffraction grating which diffracts the light beam from the light source
Implementation Method 2
a mirror which is placed on an optical path between the mixing portion and the non-polarization beam splitter, and which reflects the diffracted light beam from the mixing portion
Implementation Method 3
a polarizing plate which allows a corresponding one of the diffracted light beams split by the non-polarization beam splitter, to be transmitted through the polarizing plate
Implementation Method 4
a quarter wave plate which is placed in one of the detectors, and which is disposed between the polarizing plate and the non-polarization beam splitter
Implementation Method 5
a light receiving element which receives the diffracted light beam that are transmitted through the polarizing plate
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A photoelectric encoder which can be miniaturized is provided. A photoelectric encoder 10 includes: a light source 11; a scale 12; a mixing portion (polarization beam splitter) 13 which mixes a plurality of diffracted light beams A1, A2 reflected from the scale 12; a non-polarization beam splitter 143 which splits the diffracted light beam mixed by the mixing portion 13, into a plurality of light beams; a plurality of detectors 15A, 15B; and a quarter wave plate 151 which is placed in one of the detectors 15A, 15B. The photoelectric encoder further includes a mirror 142 which is placed on an optical path between the mixing portion 13 and the non-polarization beam splitter 143, and which reflects the diffracted light beam from the mixing portion 13. The mirror 142 reflects the diffracted light beam in a direction which is parallel to the plane of the scale 12, or in a direction which is directed to the plane of the scale 12.