Absolute position miniature grating encoder readhead using fiber optic receiver channels

A receiver and channel technology, which is applied to the use of optical devices and the use of optical devices to transmit sensing components, instruments, etc., can solve the problem of coarse encoder accuracy and other problems

Inactive Publication Date: 2004-12-01
MITUTOYO CORP
View PDF4 Cites 8 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the resulting encoder has a coarser precision

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Absolute position miniature grating encoder readhead using fiber optic receiver channels
  • Absolute position miniature grating encoder readhead using fiber optic receiver channels
  • Absolute position miniature grating encoder readhead using fiber optic receiver channels

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0033] Figure 1 shows a first general embodiment of an absolute position fiber optic readhead arrangement 20 according to the invention. As shown in Figure 1, the absolute position fiber optic read head configuration 20 includes a ferrule 40 having an alignment groove 45 and an alignment collar 50, and it includes three read head sections 60, 60' and 60". The teachings of U.S. Patent Application No. 10 / 298,312 to form the read head sections 60, 60' and 60", U.S. Patent Application No. 10 / 298,312 entitled "High Accuracy Miniature Grating Encoder Read Head Using Fiber Optic Receiver Channel", Filed November 15, 2002, which is commonly assigned and is hereby incorporated by reference in its entirety. As will be described in more detail below, each readhead portion 60, 60' and 60" corresponds to a scale track 80, 80', 80", respectively, which is included on a scale 90 which 90 is formed on a substrate 95. In one embodiment, as part of an absolute position system, the three scale ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

An absolute position fiber optic encoder readhead having multiple readhead portions for sensing the displacement of respective scale grating tracks of a scale is disclosed. The detector channels of the readhead portions are fiber optic detector channels having respective phase grating masks. The fiber optic encoder readhead portions are configured to detect the displacement of a self-image of a respective scale grating track of the scale. In various exemplary embodiments, the fiber optic readhead portions are constructed according to various design relationships that provide a relatively high signal-to-noise ratio. Accordingly, high levels of displacement signal interpolation may be achieved, allowing submicrometer displacement measurements. The fiber optic encoder readhead portions may be assembled in a particularly accurate and economical manner and may be provided in a package with dimensions on the order of 1-2 millimeters, resulting in a very small overall absolute readhead dimension that is dependent on the number of readhead portions that are incorporated. Optical fiber receiver channels carrying binary optical signals derived from a scale code track may be provided in the readhead, to provide an extended absolute measurement range.

Description

technical field [0001] In general, the present invention relates to displacement detection optical encoders, and in particular to absolute position optical encoders, which use optical fibers as receiver elements for providing extremely compact high precision absolute position system ). Background technique [0002] A variety of motion or position encoders are currently available for detecting linear, rotary, or angular motion. These encoders are generally based on optical systems, magnetic scales, inductive or capacitive sensors. Some of these encoders are designed to make relative rather than absolute measurements. In such relative position encoders, where measurement is generally performed by detecting the relative position change of the scale relative to a reference position, it is necessary to continuously detect changes in the scale pattern so that repetitions of said pattern can be counted. The relative measurements require establishing a new reference or zero posit...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): G01D5/30G01D5/347
CPCG01D5/34723
Inventor 约瑟夫·D·托比亚森金·W·阿瑟顿
Owner MITUTOYO CORP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products