Suppression of Noise to Obtain a High-Performance Low-Cost Optical Encoder

<table class="algorithm-group"><tr><td><table class="algorithm" id="alg1"><tr><td colspan="2">For <span class="nowrap"><svg height="9.75571pt" id="M88" style="vertical-align:-1.11981pt" version="1.1" viewbox="-0.0498162 -8.6359 32.2343 9.75571" width="32.2343pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M822 650H589L583 622C660 617 677 607 674 561C672 534 664 481 647 390L600 137H596L273 650H126L120 622C176 620 194 615 207 594C221 571 225 557 214 504L161 257C141 166 129 112 121 85C108 42 83 30 29 28L23 0H260L266 28C193 33 173 42 176 89C178 122 186 172 202 255L256 527H259L583 -8H612L690 390C708 481 720 535 728 558C744 603 756 619 816 622L822 650Z" id="g113-79"></path></g><g transform="matrix(.013,0,0,-0.013,14.542,0)"><path d="M531 285V335L57 550V494L473 310L57 127V71L531 285ZM531 -40V10H57V-40H531Z" id="g117-94"></path></g><g transform="matrix(.013,0,0,-0.013,25.805,0)"><path d="M285 378C315 398 338 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336 -12 358 -12C381 -12 423 2 477 80L460 100C434 74 408 54 398 54C385 54 374 65 351 107C326 154 282 241 263 299C296 332 351 377 403 377C424 377 436 372 445 368C449 366 456 368 462 375C472 386 480 402 480 416Z" id="g113-108"></path></g></svg> number of angular measurements can be obtained from the possible number of combinations between phases, utilizing the phase-shifting (PS) general form <svg height="17.3996pt" id="M90" style="vertical-align:-5.808199pt" version="1.1" viewbox="-0.0498162 -11.5914 188.935 17.3996" width="188.935pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M475 507C475 612 440 712 326 712C139 712 23 420 23 215C23 96 58 -12 180 -12C369 -12 475 293 475 507ZM391 522C391 486 387 448 379 394H126C155 538 222 677 310 677C386 677 391 571 391 522ZM373 346C344 193 283 22 189 22C126 22 106 114 106 196C106 243 111 293 118 346H373Z" id="g113-230"></path></g><g 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Journal of Sensors

alg1

Algorithm 1

Algorithm 1: Suppression of Noise to Obtain a High-Performance Low-Cost Optical Encoder 