{"id":6514,"date":"2012-07-19T16:12:13","date_gmt":"2012-07-19T09:12:13","guid":{"rendered":"https:\/\/banbientan.com\/?p=6514"},"modified":"2012-07-19T16:12:13","modified_gmt":"2012-07-19T09:12:13","slug":"tong-quan-ve-cong-nghe","status":"publish","type":"post","link":"https:\/\/hunglong.banbientan.com\/?p=6514","title":{"rendered":"T\u1ed5ng quan v\u1ec1 C\u00f4ng ngh\u1ec7"},"content":{"rendered":"

Gi\u1edbi thi\u1ec7u\"\"<\/a><\/strong><\/span>
\nTrong ph\u1ea7n n\u00e0y, ch\u00fang ta s\u1ebd t\u00ecm hi\u1ec3u thu\u1eadt ng\u1eef ch\u00ednh v\u00e0 c\u00e1c nguy\u00ean t\u1eafc ho\u1ea1t \u0111\u1ed9ng c\u1ee7a c\u1ea3m bi\u1ebfn s\u1ee3i quang. Tr\u01b0\u1edbc ti\u00ean, ch\u00fang ta s\u1ebd xem ho\u1ea1t \u0111\u1ed9ng c\u1ee7a B\u1ed9 khuy\u1ebfch \u0111\u1ea1i v\u00e0 sau \u0111\u00f3 s\u1ebd xem c\u00e1c s\u1ee3i quang.
\nB\u1ea1n s\u1ebd th\u1ea5y c\u00f3 nhi\u1ec1u \u0111i\u1ec3m t\u01b0\u01a1ng \u0111\u1ed3ng gi\u1eefa c\u00f4ng ngh\u1ec7 c\u1ea3m bi\u1ebfn quang \u0111i\u1ec7n th\u00f4ng th\u01b0\u1eddng v\u00e0 c\u1ea3m bi\u1ebfn s\u1ee3i quang v\u00e0 ph\u1ea7n n\u00e0y s\u1ebd gi\u00fap b\u1ea1n hi\u1ec3u \u0111\u01b0\u1ee3c nh\u1eefng \u0111i\u1ec3m kh\u00e1c bi\u1ec7t.
\nB\u1ea1n c\u00f3 th\u1ec3 tham kh\u1ea3o b\u1ea3ng ch\u00fa gi\u1ea3i thu\u1eadt ng\u1eef c\u00f3 s\u1eb5n trong thanh menu \u1edf \u0111\u1ea7u trang.
\nB\u1ed9 ph\u1eadn C\u1ea5u th\u00e0nh<\/span><\/strong><\/span><\/span><\/span>
\nC\u1ea3m bi\u1ebfn s\u1ee3i quang hi\u1ec7n \u0111\u1ea1i nh\u01b0 Omron E3X bao g\u1ed3m c\u00e1c b\u1ed9 ph\u1eadn c\u01a1 b\u1ea3n nh\u01b0 nhau.\"\"<\/a><\/strong>
\nB\u1ed9 khuy\u1ebfch \u0111\u1ea1i:<\/strong> bao g\u1ed3m ngu\u1ed3n s\u00e1ng, b\u1ed9 x\u1eed l\u00fd \u00e1nh s\u00e1ng h\u1eaft l\u1ea1i, c\u00f3 giao di\u1ec7n v\u1eadn h\u00e0nh \u0111\u1ec3 thi\u1ebft l\u1eadp ho\u1ea1t \u0111\u1ed9ng c\u1ee7a c\u1ea3m bi\u1ebfn v\u00e0 c\u00f3 t\u00edn hi\u1ec7u \u0111\u1ea7u ra<\/strong> \u0111\u1ebfn thi\u1ebft b\u1ecb x\u1eed l\u00fd kh\u00e1c.
\nS\u1ee3i quang:<\/strong> d\u1eabn h\u01b0\u1edbng \u00e1nh s\u00e1ng t\u1eeb b\u1ed9 khuy\u1ebfch \u0111\u1ea1i \u0111\u1ebfn v\u1eadt th\u1ec3 v\u00e0 d\u1eabn h\u01b0\u1edbng \u00e1nh s\u00e1ng ph\u1ea3n h\u1ed3i ng\u01b0\u1ee3c tr\u1edf l\u1ea1i b\u1ed9 khuy\u1ebfch \u0111\u1ea1i \u0111\u1ec3 x\u1eed l\u00fd.
\n\u0110\u1ea7u S\u1ee3i quang:<\/strong> l\u00e0 ph\u01b0\u01a1ng ti\u1ec7n \u0111\u1ec3 d\u1eabn h\u01b0\u1edbng th\u00eam v\u00e0 \u0111\u1ea3m b\u1ea3o s\u1ee3i quang \u0111\u01b0\u1ee3c l\u1eafp \u0111\u1eb7t ch\u1eafc ch\u1eafn v\u1ec1 c\u01a1 h\u1ecdc. Theo t\u00f9y ch\u1ecdn, \u0111\u1ea7u s\u1ee3i quang c\u00f3 th\u1ec3 l\u1eafp th\u00eam c\u00e1c th\u1ea5u k\u00ednh, \u0111\u1ec3 \u0111\u1ecbnh h\u00ecnh tia s\u00e1ng khi ra kh\u1ecfi s\u1ee3i quang ho\u1eb7c thay \u0111\u1ed5i g\u00f3c nh\u1eadn c\u1ee7a \u00e1nh s\u00e1ng ph\u1ea3n h\u1ed3i.
\nHi\u1ec7n nay c\u00f3 r\u1ea5t nhi\u1ec1u k\u1ebft h\u1ee3p lo\u1ea1i s\u1ee3i quang\/\u0111\u1ea7u s\u1ee3i quang kh\u00e1c nhau. Ch\u00fang ta s\u1ebd t\u00ecm hi\u1ec3u th\u00eam v\u1ec1 nh\u1eefng lo\u1ea1i n\u00e0y sau trong kh\u00f3a h\u1ecdc.
\nC\u1ea3m bi\u1ebfn s\u1eed d\u1ee5ng m\u1ed9t s\u1ee3i quang \u0111\u1ec3 chi\u1ebfu s\u00e1ng v\u1eadt th\u1ec3 v\u00e0 m\u1ed9t s\u1ee3i quang kh\u00e1c \u0111\u1ec3 mang \u00e1nh s\u00e1ng ph\u1ea3n chi\u1ebfu<\/strong> tr\u1edf l\u1ea1i b\u1ed9 khu\u1ebfch \u0111\u1ea1i.\u00a0 Trong v\u00ed d\u1ee5 \u1edf b\u00ean ph\u1ea3i, c\u1ea3 hai s\u1ee3i quang ch\u1eadp l\u1ea1i l\u00e0m m\u1ed9t \u0111\u1ec3 t\u1ea1o th\u00e0nh m\u1ed9t thi\u1ebft b\u1ecb nh\u1ecf g\u1ecdn c\u00f3 kh\u1ea3 n\u0103ng v\u1eeba chi\u1ebfu s\u00e1ng v\u1eeba c\u1ea3m nh\u1eadn s\u1ef1 hi\u1ec7n di\u1ec7n c\u1ee7a v\u1eadt th\u1ec3 nh\u1ecf.
\nTrong c\u1ea5u h\u00ecnh thu ph\u00e1t \u0111\u1ed9c l\u1eadp minh h\u1ecda b\u00ean d\u01b0\u1edbi, c\u00e1c s\u1ee3i quang t\u00e1ch bi\u1ec7t v\u00e0 \u0111\u01b0\u1ee3c \u0111\u1eb7t h\u01b0\u1edbng v\u00e0o nhau. Trong c\u1ea5u h\u00ecnh n\u00e0y, v\u1eadt th\u1ec3 s\u1ebd l\u00e0m gi\u00e1n \u0111o\u1ea1n ch\u00f9m s\u00e1ng<\/strong> gi\u1eefa hai \u0111\u1ea7u s\u1ee3i quang.
\n\"\"<\/a>\u00a0\"\"<\/a>
\nC\u01b0\u1eddng \u0111\u1ed9 v\u00e0 Ng\u01b0\u1ee1ng\"\"<\/a><\/strong><\/span>
\n\u00c1nh s\u00e1ng ph\u1ea3n x\u1ea1<\/span> t\u1eeb v\u1eadt th\u1ec3 ho\u1eb7c \u00e1nh s\u00e1ng do v\u1eadt th\u1ec3 l\u00e0m gi\u00e1n \u0111o\u1ea1n<\/span> s\u1ebd tr\u1edf l\u1ea1i b\u1ed9 khuy\u1ebfch \u0111\u1ea1i \u0111\u1ec3 x\u1eed l\u00fd.
\nGi\u00e1 tr\u1ecb\u00e1nh s\u00e1ng t\u1edbin\u00e0y sau \u0111\u00f3 s\u1ebd \u0111\u01b0\u1ee3c so s\u00e1nh v\u1edbi gi\u00e1 tr\u1ecbng\u01b0\u1ee1ng. Nh\u01b0 trong c\u1ea3m bi\u1ebfn quang \u0111i\u1ec7n th\u00f4ng th\u01b0\u1eddng,\u0111\u1ea7u rac\u1ee7a c\u1ea3m bi\u1ebfn ph\u1ee5 thu\u1ed9c v\u00e0o vi\u1ec7c\u00e1nh s\u00e1ng t\u1edbi\u1edf tr\u00ean hay \u1edf d\u01b0\u1edbigi\u00e1 tr\u1ecb ng\u01b0\u1ee1ngt\u1ea1i b\u1ea5t k\u1ef3 th\u1eddi \u0111i\u1ec3m n\u00e0o.
\n\u1ede \u0111\u00e2y ch\u00fang ta th\u1ea5y \u0111\u1ea7u raON (B\u1eacT)n\u1ebfu \u00e1nh s\u00e1ng t\u1edbi\u1edf tr\u00eanng\u01b0\u1ee1ng v\u00e0OFF (T\u1eaeT)n\u1ebfu \u00e1nh s\u00e1ng t\u1edbi\u1edf d\u01b0\u1edbi ng\u01b0\u1ee1ng.
\nS\u00e1ng B\u1eacT \/ T\u1ed1i B\u1eacT\"\"<\/a><\/span><\/strong><\/span><\/span><\/span>
\nTrong m\u1ed9t s\u1ed1 \u1ee9ng d\u1ee5ng, thi\u1ebft b\u1ecb c\u00f3 th\u1ec3 c\u1ea7n \u0111\u1ea7u ra c\u1ea3m bi\u1ebfn \u0111\u1ea3o ng\u01b0\u1ee3c;\u00a0OFF (T\u1eaeT)<\/span> n\u1ebfu \u1edf tr\u00ean<\/strong> ng\u01b0\u1ee1ng v\u00e0 ON (B\u1eacT) n\u1ebfu \u1edf d\u01b0\u1edbi<\/strong>.\u00a0 So s\u00e1nh s\u01a1 \u0111\u1ed3 tr\u01b0\u1edbc v\u1edbi s\u01a1 \u0111\u1ed3 n\u00e0y.
\nB\u1ea1n c\u00f3 th\u1ec3 d\u00f9ng c\u00f4ng t\u1eafc tr\u00ean b\u1ed9 khuy\u1ebfch \u0111\u1ea1i \u0111\u1ec3 ch\u1ecdn ho\u1ea1t \u0111\u1ed9ng S\u00e1ng B\u1eacT<\/strong> ho\u1eb7c T\u1ed1i B\u1eacT<\/strong> n\u1ebfu c\u1ea3m bi\u1ebfn “s\u00e1ng” ho\u1eb7c “t\u1ed1i” B\u1eacT \u0111\u1ea7u ra.
\nCh\u00fang ta th\u1ea5y r\u1eb1ng c\u1ea3m bi\u1ebfn quang \u0111i\u1ec7n th\u00f4ng th\u01b0\u1eddng c\u0169ng c\u00f3 c\u00f9ng nguy\u00ean t\u1eafc ho\u1ea1t \u0111\u1ed9ng, v\u00ec v\u1eady kh\u00e1i ni\u1ec7m n\u00e0y t\u01b0\u01a1ng \u0111\u1ed1i quen thu\u1ed9c.
\nH\u01b0\u1edbng d\u1eabn \/ \u0110i\u1ec1u ch\u1ec9nh\"\"<\/a><\/span><\/strong><\/span><\/span><\/span>
\nB\u1ed9 khuy\u1ebfch \u0111\u1ea1i s\u1ee3i quang k\u1ef9 thu\u1eadt s\u1ed1 c\u1ee7a OMRON c\u00f3 ph\u1ea1m vi d\u00f2 t\u00ecm t\u1eeb 0000 \u0111\u1ebfn 4000 l\u1ea7n<\/span><\/span><\/a>. Gi\u00e1 tr\u1ecb ng\u01b0\u1ee1ng c\u0169ng c\u00f3 ph\u1ea1m vi t\u1eeb 0000 \u0111\u1ebfn 4000 l\u1ea7n.
\n\u00c1nh s\u00e1ng \u0111\u01b0\u1ee3c \u0111o v\u00e0 so s\u00e1nh v\u1edbi gi\u00e1 tr\u1ecb ng\u01b0\u1ee1ng. N\u1ebfu \u00e1nh s\u00e1ng t\u1edbi \u1edf tr\u00ean ng\u01b0\u1ee1ng, \u0111\u1ea7u ra ON (B\u1eacT) v\u00e0 n\u1ebfu \u00e1nh s\u00e1ng t\u1edbi \u1edf d\u01b0\u1edbi ng\u01b0\u1ee1ng, \u0111\u1ea7u ra OFF (T\u1eaeT) t\u00f9y theo c\u00e0i \u0111\u1eb7t LIGHT ON \/ DARK ON (S\u00c1NG B\u1eacT\/T\u1ed0I B\u1eacT).
\nXung quanh gi\u00e1 tr\u1ecb ng\u01b0\u1ee1ng s\u1ebd c\u00f3 m\u1ed9t d\u1ea3i nh\u1ecf, t\u1ea1i \u0111\u00f3 t\u00edn hi\u1ec7u \u0111\u1ea7u ra kh\u00f4ng \u1ed5n \u0111\u1ecbnh v\u00e0 c\u00f3 th\u1ec3 ON (B\u1eacT) ho\u1eb7c OFF (T\u1eaeT). Hi\u1ec7n t\u01b0\u1ee3ng n\u00e0y \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 hi\u1ec7n t\u01b0\u1ee3ng tr\u1ec5 (hysteresis). Trong s\u01a1 \u0111\u1ed3, v\u00f9ng tr\u1ec5 \u0111\u01b0\u1ee3c ph\u00f3ng \u0111\u1ea1i c\u1ef1c l\u1edbn.
\nB\u00e3o h\u00f2a<\/object><\/span><\/strong><\/span><\/span><\/span>
\nGi\u00e1 tr\u1ecb c\u1ee7a \u00e1nh s\u00e1ng t\u1edbi t\u0103ng v\u00e0 gi\u1ea3m khi m\u1ed9t v\u1eadt th\u1ec3 di chuy\u1ec3n qua \u0111\u1ea7u s\u1ee3i quang. Ch\u1eebng n\u00e0o gi\u00e1 tr\u1ecb \u0111\u01b0\u1ee3c x\u1eed l\u00fd \u1edf trong ph\u1ea1m vi ho\u1ea1t \u0111\u1ed9ng c\u1ee7a b\u1ed9 khuy\u1ebfch \u0111\u1ea1i<\/strong>(0000 \u0111\u1ebfn 4000 l\u1ea7n), c\u1ea3m bi\u1ebfn s\u1ebd ho\u1ea1t \u0111\u1ed9ng b\u00ecnh th\u01b0\u1eddng.
\nTuy nhi\u00ean, n\u1ebfu \u00e1nh s\u00e1ng t\u1edbi s\u00e1ng \u0111\u1ebfn n\u1ed7i gi\u00e1 tr\u1ecb t\u1edbi v\u1eabn gi\u1eef nguy\u00ean \u1edf m\u1ee9c c\u1ef1c \u0111\u1ea1i (4000 l\u1ea7n) ngay c\u1ea3 khi c\u00f3 m\u1eb7t v\u1eadt th\u1ec3 th\u00ec b\u1ed9 khuy\u1ebfch \u0111\u1ea1i \u0111\u01b0\u1ee3c coi l\u00e0 b\u00e3o h\u00f2a<\/strong>.
\nM\u1eb7c d\u00f9 b\u1ed9 khuy\u1ebfch \u0111\u1ea1i b\u00e3o h\u00f2a ngay c\u1ea3 khi ng\u01b0\u1ee1ng \u0111\u01b0\u1ee3c \u0111\u1eb7t \u1edf m\u1ee9c c\u1ef1c \u0111\u1ea1i nh\u01b0ng kh\u00f4ng c\u00f3 chuy\u1ec3n m\u1ee9c ng\u01b0\u1ee1ng v\u00e0 \u0111\u1ea7u ra c\u1ea3m bi\u1ebfn kh\u00f4ng thay \u0111\u1ed5i.
\nH\u01b0\u1edbng d\u1eabn \/ \u0110i\u1ec1u ch\u1ec9nh – 2\u00a0<\/object><\/span><\/strong><\/span><\/span><\/span>
\nDo m\u1ed7i \u1ee9ng d\u1ee5ng c\u00f3 c\u00e1c m\u1ee9c \u00e1nh s\u00e1ng thu h\u1ed3i kh\u00e1c nhau, c\u1ea7n \u0111i\u1ec1u ch\u1ec9nh b\u1ed9 khuy\u1ebfch \u0111\u1ea1i v\u00e0 ngu\u1ed3n s\u00e1ng c\u1ee7a n\u00f3.<\/strong>
\n\u0110i\u1ec1u ch\u1ec9nh (Tuning) ho\u1eb7c \u0110i\u1ec1u ch\u1ec9nh h\u01b0\u1edbng d\u1eabn (Teaching) \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n \u0111\u1ec3 tr\u00e1nh b\u00e3o h\u00f2a, cho ph\u00e9p \u0111\u1ed9 nh\u1ea1y t\u1ed1i \u0111a v\u00e0 \u0111\u1ea3m b\u1ea3o ph\u00e1t hi\u1ec7n tin c\u1eady.
\nV\u00ed d\u1ee5: \u0110i\u1ec1u ch\u1ec9nh C\u00f4ng su\u1ea5t<\/strong> <\/a>t\u1ef1 \u0111\u1ed9ng \u0111\u1eb7t m\u1ee9c ph\u00e1t s\u00e1ng l\u00fd t\u01b0\u1edfng \u0111\u1ec3 c\u00f3 \u0111\u1ed9 nh\u1ea1y t\u1ed1i \u0111a c\u1ee7a b\u1ed9 khuy\u1ebfch \u0111\u1ea1i m\u00e0 kh\u00f4ng b\u00e3o h\u00f2a.
\nH\u01b0\u1edbng d\u1eabn Hai \u0110i\u1ec3m<\/strong>, t\u1ef1 \u0111\u1ed9ng \u0111\u1eb7t gi\u00e1 tr\u1ecb ng\u01b0\u1ee1ng d\u1ef1a tr\u00ean m\u1ee9c trung b\u00ecnh<\/span> c\u1ee7a \u00e1nh s\u00e1ng thu h\u1ed3i tr\u1edf l\u1ea1i c\u1ea3m bi\u1ebfn khi c\u00f3 v\u00e0 khi kh\u00f4ng c\u00f3 v\u1eadt th\u1ec3.
\n\u0110\u1ec3 xem \u0110i\u1ec1u ch\u1ec9nh C\u00f4ng su\u1ea5t v\u00e0 H\u01b0\u1edbng d\u1eabn 2 \u0111i\u1ec3m (2-point teaching) \u1ea3nh h\u01b0\u1edfng nh\u01b0 th\u1ebf n\u00e0o \u0111\u1ebfn m\u1ee9c \u00e1nh s\u00e1ng t\u1edbi v\u00e0 ng\u01b0\u1ee1ng, nh\u1ea5p v\u00e0o TUNE (\u0110I\u1ec0U CH\u1ec8NH)<\/strong><\/span> trong h\u00ecnh.
\nC\u1ea5u tr\u00fac S\u1ee3i quang\"\"<\/a><\/span><\/strong><\/span><\/span><\/span>
\nS\u1ee3i quang l\u00e0 v\u1eadt li\u1ec7u polyme m\u1ecfng ho\u1eb7c v\u1eadt li\u1ec7u th\u1ee7y tinh m\u1ecfng truy\u1ec1n \u00e1nh s\u00e1ng qua l\u1ea1i t\u1eeb v\u1eadt th\u1ec3 \u0111ang \u0111\u01b0\u1ee3c<\/strong> ph\u00e1t hi\u1ec7n.<\/strong>
\nHai \u0111\u1eb7c t\u00ednh quan tr\u1ecdng c\u1ee7a s\u1ee3i quang li\u00ean quan \u0111\u1ebfn c\u1ea5u tr\u00fac c\u1ee7a s\u1ee3i:<\/p>\n