pISSN 1225-5475/eISSN 2093-7563
PMMA ° ⁄√» ÷ß ∏∂¶ Ƭ Ÿ¯∫‘“ ›«ª ÃΗ §∂Ø –¬æ≠
¯+§∂“¨
Fiber-Optic Pressure Sensor Using a Rugate-Structured Porous Silicon Diaphragm Coated with PMMA
Ki-Won Lee+and So-Yeon Cho
Abstract
In this research, fiber-optic pressure sensors were fabricated with rugate-structured porous silicon (RPS) diaphragms coated with PMMA (Polymethyl-Methacrylate). The reflectance spectrum of the PMMA/RPS diaphragm was almost the same as that of uncoated RPS diaphragm. However the mechanical strength of the PMMA/RPS diaphragm increased more than that of the uncoated diaphragm.
As a result, the fiber-optic sensor fabricated with PMMA/RPS diaphragm could successfully detect more high pressure difference without diaphragm damage than the highest detectable pressure difference of the sensor with normal RPS diaphragm. The response data of the fiber-optic sensor recorded as a function of pressure difference were fitted by theoretical curves. During this process, elastic moduli of the used PMMA/RPS diaphragms were obtained numerically. The dynamic response properties of the fiber-optic sensor were also investigated under continuous variation of the pressure difference conditions.
Keywords : Porous silicon, Pressure sensor, PMMA, Pressure difference, Fiber-optic sensor, Diaphragm
1. ≠ –
“≠ˆ“Í(HF) Î◊ ”°≠ ‹·§ ‘“ ‚«« ÁÿÍ≠
(anodization)° «ÿ ¶¤«¬ Ÿ¯∫‘“(Porous Silicon, PS)¬
≠— fl§ Ø∫˙ ÌŸ¯∫ ∏∂ ßÆ° ∞fl˜ ¨∏«Ì ÷Ÿ. ؘ
à Á·¶ ‚º, ◊º, ŸÃ¿ ∞˙ Óª À‚œ‚ ß— æ≠« ˆ ŒŒ≠ ÃÎœ‚ ßÿ ŸÁ— √μÈà ¯‡«Ó ‘Ÿ. ‚ºŒ¬
NO2, °∫√[1-3] Ó, ◊ºŒ¬ °∫√, œœΔˆ[4] Ó, ŸÃ¿ ∞
˙Œ¬DNA, IgG[5-8] Óà ˆÎÛ ∞˙Œ≠ ¨∏» Ÿ ÷Ÿ.
ÃØ— ¨∏Õ ı“ÓPS¶ –¬¿∞˙Œ≠ ∞Îœ‚ ß— ¨
∏μ √μ«˙Ÿ. GangopadhyayÕPramanik ¨∏◊Ï∫ „∫
‘“ ‚« ß°PS° ¸∫» ∏∂, ÔPS/Si ›«(diaphragm)ª
¶¤œÌ, –¬° ˚•PS ˛« ¸‚˚ ˙◊Ø≠ŒŒÕ –¬¿ª Ú˙Ÿ[9, 10]. Sujathaμ ØÁ—PS/Si ∏∂¶ ¶¤œ¥Ÿ[11]. ◊
ÆÌ Œ°» –¬° ˚• ›«« ظªpiezoresistorŒ ¯§‘∏
Œ· –¬ ¿ª Ú∫Ÿ ÷Ÿ. ÃØ— ¨∏È∫PS¶ –¬¿∞
˙Œ≠ ∞Îœ‚ ßÿ √μ» ±μ˚Œ ¨∏ÈŒ≠ Ú°… ˆ ÷Ÿ.
◊Ø™ Œ ÊÏ ŒPS« Œ∫؈‚ ¨Ó Ø∫ ßÆ°PS ∞˙∏
∏Œ –¬¿ª Úˆ ¯œÌ ◊ ˆˆºŒSià ›«ª ∏∫œ¬ ‰
“Œ≠ ø√° ÁΫ˙Ÿ. ˚Û≠ æ≠ŒŒÕ ‚¬«¬ –¬¿
« Œμ¬ ÁλSi ∑ ßÆ° ∑Δ˙ ˆ ÷Ÿ. ”∏ ΔœÛ –¬
¿≈£¶ Ú‚ ßÿ PS/Si ›« ß° ›”¸ÿ «¬
piezoresistor« Œ¯Ã ‰œŸ. ÃØ— Ø∞˙μ –¬¿«
ø≤ª ∑fl¬ ‰ŒÃ … ˆ ÷Ÿ.
÷Ÿ°¬ ‚∏ ¨∏« ÃØ— ‹°ª ÿπœ‚ ßÿ ÷ß ∏∂
¶ Ƭ Ÿ¯∫‘“(Rugate-structured Porous Silicon, RPS)
›«ª ÃΗ §∂Ø –¬æ≠(fiber-optic pressure sensor)°
∏Ì»Ÿ ÷Ÿ[12]. à æ≠¬ ⁄≥¸PS ›« ∏ª –¬¿Á·Œ
≠ ∞Îœ‚ ßÆ°, ¿ ¸˙ ƒ« ≈£« Ø≠≤Ã æ¸ ¨∏«
‡3% ∏Ÿ ≈Ï Ù∫40% ÃÛª ∏¥Ÿ. ‘Ÿ° à æ≠¬RPS
›«« ›Á ∫ÂÆ≥°≠ ¸˚«¬ Ø´ŒÓ ÿ„Ι(stopband)
¯÷Ζ≥ ∞Æ–˙(Department of Physics, Kongju National University)
56 Gongjudaehak-ro, Gongju, Chungnam 314-701, Korea
+Corresponding author: [email protected] (Received : May. 6, 2013, Accepted : May. 23, 2013)
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License(http://creativecommons.org/licenses/by- nc/3.0)which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
ª ÃÎœ© §–˚Œ Ê˝∏Œ ¿≈£¶ Ú‚ ßÆ° ›«Ã Ã
˜˚Œ ∞˙˙ ¢Àœˆ ¬ °à ÷Ÿ. —Ì Ã æ≠« ‹°∏
Œ¬RPS ›«« Œ∫؈‚ ¨Ó Ø∫ ßÆ° ¯§ –¬˜« μ
™Ã20 kPa Ã∏∏Œ ≈Ï ºŸ¬ Õß. ◊Ø«Œ à æ≠« ø Î∫ª Ù ßÿ≠¬ ¯§μ™« Æζ ß— ¨∏° ›Â√
‰œŸ.
ð ˚Û ª ¨∏°≠¬RPS ›«ª ÃΗ §∂Ø –¬æ≠«
¯§¸ß¶ – ߗ ˆ‹∏Œ≠, RPS ›« ß°
PMMA(Polymethyl-Methacrylate)¶ ⁄√œ© ™–˚ ≠μ°
≠≠»PMMA/RPS ›«ª ¶¤œ¥Ÿ. ◊ÆÌ Ã ›«« §–˚
Ø∫˙ à ›«ª ¯— §∂Ø æ≠« –¬¿ Ø∫ª ∂Áœ¥
Ÿ. ◊ÆÌ «Ë˚∏Œ ¯§» –¬¿ª Ö˚ ª ‚›∏Œ
— ƒªÕ √ƒπë ·˙Õ Ò≥œ¥∏Á, à ˙§°≠
PMMA/RPS ›«È« ∫∫ˈ ™Èª μ‚œ¥Ÿ.
2. «Ë Ê˝
2.1 √·« ¶¤
÷ß ∏∂¶ ƬPS¬ Ò˙◊Ã0.02 Ÿ.cmŒ(100)Ê‚ ‹·
§ ‘“‚«(Nilaco, Si-500440)ª °∫√à ÒÆ»15% HF Î◊
”°≠ ÁŒƒ¸ ¸˘–μŒ ÁÿÍ≠œ© ¶¤«˙Ÿ. ÁŒƒ¸
∫S. Ilyas ◊Ï« Ê˝˙ øœœ‘step functionª ÃÎœ© Ÿ
Á˚∏Œ ¸∫«˙Ÿ[13]. Step function∫ ¡Œ◊• °…— ¸¯
¯ fi ‚(Agilent, E3634A)Õ LabVIEW 8.5(National Instruments)¶ ÃÎœ© ¶¤«˙Ÿ. — ÷‚« ÁŒƒ¸∫ —
35≥« ∫‹∏Œ ∏ÈÓ≥Ì, ÷“Õ ÷Î ¸˘–μ ™∫ ¢¢
15.0˙50.0 mA/cm2Ã˙Ÿ. ƒ¸« — ÷‚ ™∫7.0 sŒ ̧«
˙∏Á, ÷ß ∏∂¶ ¸∫œ‚ ß— ƒ¸« ÷‚ˆ¬100÷‚Œ Ì
§œ¥Ÿ.
¶¤» ÷ß ∏∂¶ ƬPS¬Si ‚« ß° ©¸˜ Œ¯«Ó ÷ Ÿ. ◊Ø«ŒRPS ›«ª ¶¤œ‚ ßÿ≠¬Si ‚«∏ŒŒÕ ÷ß
∏∂¶ ƬPS ˛∏ª œ¸˜ –Æÿfl∏ —Ÿ. ◊±• Ãà ∏È
Ó¯RPS ›« ß°PMMA¶ ⁄√œ¬ Õ∫ Œ∫؈‚ ¨Ó ›
«« Ø∫ ßÆ° ˆÿ˜ ÓΔŸ. ◊°≠ ª ¨∏°≠¬PS ˛« œ
‹∫ ‚«˙ –Æ«˙∏™ °Â⁄Ƭ ©¸˜ ‚«˙ ŸÓ÷¬
semi-RPS¶ fl£‹ËŒ≠ ¶¤œÌ, à √· ß°PMMA¶ ⁄√
œ¥Ÿ. ◊ÆÌ ◊ ƒ° ›«« °Â⁄ƶ ‚«∏ŒŒÕ œ¸˜ – Æ√¥∏Œ·PMMA/RPS ›«ª ¶¤œ¥Ÿ. Semi-RPS¬ ¶¤
˜ƒ« ÷ß ∏∂¶ ƬPS¶ 3.3% HF Î◊ ”°≠13.0 mA/cm2« œ§— ¸˘–μŒ50.0 s ø» Ø ÁÿÍ≠‘∏Œ·
¶¤«˙Ÿ.
PMMA –ª« Ù˙Æ(molar mass)∫25,000 g/mol Ã˙Ì,
Î≈Œ¬99.5%« ÁÁ£Ã ÁΫ˙Ÿ. PMMA Î◊« Ûμ¬
PMMA –ª« ˙Æ˙ ÁÁ£ Œ«« Ò≤ª ≠Œ fiÆœ©33.3, 50.0, 100.0 g/LŒ ∂˝œ¥Ÿ. ¶¤»PMMA Î◊∫ ∫…⁄Õ (JDtech, JSP4A)¶ ÃÎœ© ß°≠ ≥Ì—semi-RPS ß° ⁄√
«˙Ÿ. PMMA Î◊∫1000 rpm°≠semi-RPS ߌ ÷‘«˙
∏Á, ÷‘ ƒ1500 rpm°≠60.0 s ø» ؈«˙Ÿ. ⁄√à °≠
ƒ √·¬100… Œ ؈«¬ ¿Ï°≠10–£ ≠≥Æ«˙Ÿ. ∂ˆ
∑∏Œ semi-RPS« ¯Èà ‚«∏ŒŒÕ –Æ ∏Œ·, PMMA/RPS ›«Ã ÚÓ≥Ÿ. ¶¤»PMMA/RPS ›«« •È˙
‹È ¿∫ ÷Á¸⁄ˆÃÊ(Hitachi, S-4800)∏Œ ¸˚«˙Ÿ. 2.2 «Ë°« ∏∫
Fig. 1∫ ª ¨∏°≠ ¶¤— §∂Ø æ≠√∫¤« ≥´μß.
◊≤˙ ∞ÃPMMA/RPS ›«∫ ¯Î¸ ¸ Á∏Œ ˝‰sensor tipß° ı©≥Ÿ. ◊ ›«« Û‹∫ ΂–P1° ΂«˙Ì, œ‹
∫ ¯¯fl¡(KNF, N816.3KT.18)Õleak valve° «ÿ ∂˝«¬
–¬P2° ΂«˙Ÿ. ◊Ø«ŒPMMA/RPS ›«« Á‹°¬P1- P2=RP« –¬˜° Œ°»Ÿ. ¯Î¸ ¸ ªŒ°¬d=600≠ ⁄Ó
˜Êª Ƭ §∂Ø™±(bare optical fiber)(Thorlab, BFL-600)
à ‘«˙Ÿ. à §∂Ø« °∫sensor tip« °∏ŒŒÕh=1.0
ø10-3m Δ°° ̧«˙Ÿ. ◊ÆÌ Ÿ• — °∫connector¶ Ã
Îœ© –‚§∂Ø(bifurcated optical fiber)(Ocean optics, QBIF600-UV/VIS)Õ ¨·«˙Ÿ. –‚§∂Ø« Á°°¬ ¢¢
§¯Œ ÷∫Ÿ-“Œ’ •¡(Ocean optics, LS-1)Õ –§‚
(Ocean optics, USB2000+)° ◊≤≥≥ ¨·«˙Ÿ. ◊Ø«Œ §
¯°≠ Ê‚» ˚∫ –‚§∂ØÕ §∂Ø™±ª ¯‡œ©
PMMA/RPS ›«« œ‹ª ∂Á—Ÿ.
Fig. 1. Schematic diagram of a fiber-optic sensor with a PMMA/RPS diaphragm.
◊ÆÌ ◊ ›«∏ŒŒÕ ›Á» ˚« œŒ¬ ™¯∏Œ §∂Ø™±
˙ –‚§∂ض ÊØœ© –§‚Œ ¸fi»Ÿ. ö Îÿ √·°≠
›Á«¬ ›Á ∫ÂÆ≥à ¯§»Ÿ.
PMMA/RPS ›«° …Ƭ RP« ¸™∫Fig. 1°≠Õ ∞à ¸
∂Î –¬æ≠(Vernia, GPS-BTA)¶ æ≠ ¡° ¨·œ© «√£
∏Œ ¯§«˙Ÿ.
3. Ö
ÚÚ—PMMA/RPS ›«°≠ œ§— ≈Æ∏≠ ≥Ó¯ §∂ØŒ ŒÕ ˚à ∂Á«Ì ÷ª ß, ∂Á» ˚« ÛÁÆ∫ ›«°≠ ›Á
» ƒ Ÿ√ §∂ØŒ Á‘Á»Ÿ. ◊±• Fig. 1˙ ∞à PMMA/RPS ›«« Á‹° –¬˜° …ÆÈ, ›«∫ –¬Ã ∑∫
∏Œ ¡Ó¯Ÿ. ◊ØÈ ›«∏ŒŒÕ ›Á«Ó §∂ØŒ Á‘Á œ¬ ˚« ≠μ¬ ›«Ã ÚÚ“ ß ∏Ÿ “—Ÿ. ÃÕ ∞à §∂
ØŒ Á‘Áœ¬ ˚« ≠μ¶ ¯§œÌ –ÆœÈ ›«« Á‹° …
∞ –¬˜« ©‚° Η §∏¶ ∏“ ˆ ÷Ÿ.
–¬˜° «ÿ ظ«¬PMMA/RPS ›«ª ÃÛ˚Œ ˜∞›Á È∏Œ £÷œÈ, ›«Ã ÚÚ“ ßÕ Ò≥œ© ¡Ó¯ ›«°≠ › Á«Ó §∂ØŒ Á‘Áœ¬ ˚« ≠μØ≠≤∫ ŸΩ« ƒ∏Œ ÷ Ó¯Ÿ[12].
(1)ƒ°≠I0¬ ›«Ã ÚÚ“ ß ¯§» ˚« ≠μÃÌ, K¬ Ÿ
Ω˙ ∞Ÿ.
(1)ƒ˙(2)ƒ°≠d¬ ˚ª ∂ÁœÌ Ÿ√ fiΔÈì §∂Ø™
± core« ›ˆß, r∫ PMMA/RPS ›«« ›ˆß, h¬ PMMA/RPS ›«∏ŒŒÕ §∂Ø™± °‹Óˆ« ≈Æß. ◊Æ
ÌfÕf¢∫ –¬˜RP° Œ°«‚ ¸˙ ƒ« ˜∞È« °∏Œ
≠ ŸΩ˙ ∞à ¢¢ ÷Ó¯Ÿ[12].
(3)ƒ˙(4)ƒ°≠Y¬Pa« ‹ß¶ Ƭ ›«« ∫∫ˈß.
4. «Ë ·˙
Fig. 2¬ Ûμ 50.0 g/L« PMMA Î◊∏Œ ⁄√»
PMMA/RPS ›«« ¿ª ÷Á¸⁄ˆÃÊ∏Œ ¸˚— ÃÈà Ÿ. √·« °Â⁄Æ Œ–ª ¸˚œ¥‚ ßÆ° ⁄√»PMMA ˛
”∏ ΔœÛ ◊ Δ°° ÷¬RPS ˛« •È˙ ªŒ ¿μ ø√°
ÚÓ≥Ÿ. RPS ˛« ªŒ¬ ˆπ∫ ú¯Èà ´ˆ˜ ¸∫«Ó
÷Ωª ¸˚“ ˆ ÷Ÿ. à ú¯È« ©‚¬ ÁÿÍ≠ ˙§°≠
≥§» ÁŒƒ¸ ¸˘–μ ™° «∏œ‚ ßÆ°, Ìà ʂ∏Œ ÷
‚˚Œ ©‚ ‚Ô‚¶ Ƭ ˛Ã ¸∫»Ÿ(Fig. 2°≠¬ ÌƘ ∏
–«Ó ™∏™ˆ Ω). RPS ˛« •È∫ ÁŒƒ¸ ÁÿÍ≠ ¸˘
–μ« √¤ ™Œ15.0 mA/cm2Œ ÁÿÍ≠«˙‚ ßÆ° ú¯
« ©‚° Δ÷ ¤‘ ¸˚»Ÿ. ÃRPS ˛ß°¬ ⁄√»PMMA ˛
à ¸˚»Ÿ. à ˛Ã ÛÁ˜ ≈Ù¥‘ ¸˚«¬ Õ∏Œ ∏Δ, ⁄√
à ’˙œ‘ ÃÁÓ¯ Õ∏Œ «‹“ ˆ ÷Ÿ. ð ˚ÛFig. 2¬
ª ¨∏°≠ Ò˚∏Œ œ¬PMMA/RPS ›«« ∏∂° ∫¯˚∏
Œ ’˙œ‘ ¶¤«˙Ωª ™∏ΩŸ.
RPS ›«« ¸¸˚Œ §–˚ Ø∫ÃPMMA/RPS ›«°≠μ
øœœ‘ ؈«Ófl —Ÿ. ∏œPMMA/RPS ›«« ›Á ∫ÂÆ
≥°≠ Ø´ŒÓ ÿ„Ιà ı ÃÛ ¸˚«ˆ ≈™ ©‘ “«
Ó ˆ∞ŸÈ –¬¿ª Ú‚ ß— ≈£Œ≠ ÿ„Ιª ı ÃÛ ∞ Γ ˆ ¯‚ ßÆß. Fig. 3∫ ö ÆŒœ‚ ßÿRPSÕ50.0 g/L« Ûμ¶ Æ¬PMMA Î◊∏Œ ⁄√»PMMA/RPS ›««
›Á ∫ÂÆ≥Ȫ ¢¢ ¯§œÌ Ò≥— Õß. ◊≤˙ ∞à Œ
√·« ›Á ∫ÂÆ≥∫ ≈« øœœ¥Ÿ. ÔPMMA/RPS ›«°
≠μRPS ›«°≠Õ ∞à شŒÓ ÿ„Ιà ◊ÎŒ ¸˚«Á
÷οÏÆμ498 nm°≠ ©¸˜ ؈«˙Ÿ. à ·˙¬PMMA
⁄√ÃRPS›«« §–˚ Ø∫° ´ 삪 ÷ˆ ∏Á, PMMA/
RPS ›«μ §∂Ø –¬æ≠« –¬¿Á·Œ≠ ø˙˚∏Œ
(1)
(2)
(3) (4)
Fig. 2. Scanning electron microscope image of a PMMA/RPS diaphragm.
ÃÎ… ˆ ÷Ωª «Ã—Ÿ.
Fig. 4¬50.0 g/L Ûμ« PMMAŒ ⁄√»PMMA/RPS¶ Fig. 1« æ≠ ¡ ß° √¡ıÌ ŸÁ— –¬˜°≠ ›Á ∫ÂÆ≥
« Ø≠¶ Ò≥— Õß. ©‚≠ –¬˜° Œ°«ˆ ∫0.0 kPa
°≠ ¯§» ∫ÂÆ≥ªFig. 3«PMMA/RPS« ∫ÂÆ≥˙ Ò≥
ÿ º ß, øœ— ∂««PMMA/RPSœˆÛμ ∫ÂÆ≥« Á˙
÷Î ¿ÏÆ ƒÂà ≠Œ Ÿ£Ÿ. ◊ Ãج ´ ©‚«RPS ›«°
∏∂˚ Ò’˙∫à ∏Áœ© ß°° ˚Û ≠Œ Ÿ• §–˚ Ø∫à °«‚ ßÆß. ◊Ø«Œ ´ ©‚«RPS ›«Ã ¤‘ fl¡¯ ƒ æ≠ √∫¤ ß° ¯» ›«È∫ ≠Œ Ÿ• ›Á ∫ÂÆ≥ª ∏œ ˆ ÷Ÿ. ◊≤ˆÛμ fl‰— Õ∫PMMA˛« Ø´° ˚Û øœ—
ß°°≠ ¯§» ›Á∫ÂÆ≥∫Fig. 3°≠Õ ∞à ≈« øœœŸ
¬ Õß. ‰‡œÈFig. 3˙4°≠ ¸˚«¬ ›Á∫ÂÆ≥« Á
˙ ÷Î ¿ÏÆ ƒÂ« ˜Ã¬ –¬˜° «— ÕÃ ΔœÛPMMA/
RPS ˛⁄º«›Á∫ÂÆ≥Ã≠ŒŸ£‚ßÆ”ª‡˘Ÿ.
Fig. 4° ˚£È, ›«« Á‹° …Ƭ RP« ™Ã ı°“ˆœ
ÿ„Ι« ÷Î ¿ÏÆ ƒÂ∫ Øœˆ Ì, ◊ ≠μ¬ Ÿÿ˜
“ ª ÆŒ“ ˆ ÷Ÿ. ◊ÆÌRPS ›«« ÊÏ ‡20.0 kPaÃ
˙«¬ –¬˜°≠ Œ≠Æ ˆ»¯ ˆÛ[12]˙ Ò≥œ©, PMMA/RPS ›«∫50.0 kPa« –¬˜° Œ°«ıÛμ ©¸˜
؈ ∏Œ· ›Á ∫ÂÆ≥à ¯§… ˆ ÷˙Ÿ. ª «Ë« ÊÏ Fig. 1« √∫¤Ã Δ˜ ÷˚≠ «ˆ ¯ÿ50.0 kPa∏Ÿ ´ –¬˜
¬ √·° Œ°“ ˆ ¯˙Ÿ. ÃÕª »—ŸÈ ª ¨∏°≠ ¶¤
—PMMA/RPS ›«∫50.0 kPa ÃÛ« –¬˜°≠μ ©¸˜ ¸
¬¶ ؈“ ˆ ÷Ωª ¸¤“ ˆ ÷Ÿ. ∏Ÿ –∫ –¬¸ß°≠«
«Ë∫ «Ë√∫¤« ∫…ª ıÌ ‚Û√≤ ƒ° ‚ƒ ¨∏°≠ ˆ
‡“ π§ÃŸ.
ÏƬ –¬¿« »§∫˙ Œμ ¯È°≠ ψ— Ø∫ª ∏ ìPMMA« ÷˚Ûμ¶ ∂Áœ‚ ßÿ, ≠Œ Ÿ• Ûμ«
PMMAŒ ⁄√»PMMA/RPS ›«Èª ¶¤œ¥Ÿ. ◊ÆÌ ◊ ›
«È° Îÿ –¬˜« ‘ˆŒ≠ ÿ„Ι« ÷Î ¿ÏÆ ≠μ« Ø
≠, Ô –¬¿« Ø≠¶ ∂Áœ¥Ÿ. ◊ ·˙¬Fig. 5° °∏Œ
≠ ¶√«˙Ÿ. ◊≤°≠ ∂߸ °È∫PMMA° ⁄√«‚ ¸ RPS ›«« –¬¿ÃŸ. ’°≠ ‚˙— ŸÕ ∞à ›«« Œ≠
ˆ‚ ¨Ó Ø∫ ßÆ°0-20 kPa¸ß°≠∏ ¯§… ˆ ÷˙Ÿ.
—Ì ◊≤°≠ Á¢¸, ø◊ÛÃ, Ô¢¸ °È∫ ¢¢100.0, 50.0, ◊ÆÌ33.3 g/L«PMMA° ⁄√»PMMA/RPS ›«È«
–¬¿ •ÃÕß. ◊≤˙ ∞ÃPMMA Î◊« Ûμ° ˚Û √
·È« –¬¿« §μ¬ ≠Œ fi˙Ÿ. RPS ›«« –¬¿ª
‚ÿ∏Œ, 100.0 g/L« ÛμŒ ¶¤»PMMA/RPS ›«∫ ¿«
Œμ° °Â Ù‘ ™∏μŸ. ◊Ø™ ◊≤°≠Õ ∞à ¿« Ø≠
° ≈Ï “’œœ© »§∫ ¯È°≠ ∑∫ Ø∫ª ∏¥Ÿ. ð Ò
ÿ50.0 g/L« ÛμŒ ¶¤»PMMA/RPS¬ Œμ¬ ¶œ ∑∏
™ Ê‚ ÷¬ ¨”˚Œ Ø≠¶ ∏© »§∫à ψœ¥Ÿ. ◊ÆÌ
Fig. 3. A comparison between reflectivity spectra of the RPS and the PMMA/RPS diaphragms.
Fig. 4. A comparison between reflectivity spectra measured from a fiber-optic pressure sensor with a PMMA/RPS diaphragm at various pressure differences.
Fig. 5. Response curves to the pressure as measured from the RPS and the PMMA/RPS diaphragms coated with PMMA solutions of different concentrations.
33.3 g/L« ÛμŒ ¶¤»PMMA/RPS¬ ⁄√¸RPS ›«˙ ≈
« ØÁ— Ø≠¶ ∏¥Ÿ.
PMMA Î◊« Ûμ° ¨ˆœ °∫μ ÙΔˆ‚ ßÆ°PMMA˛
« ⁄√ Œ≤¬ Œ ˆ¯Ÿ. ◊Ø«Œ Ù∫ Ûμ« Î◊∏Œ ¶¤»
PMMA/RPS ›«∫ ∫∫¬Ã ı°«Ó ¿ Œμ¬ ∑ΔÆfl — Ÿ. ÃØ— ¸°°≠ ∏È50.0 g/L« ÛμŒ ¶¤»PMMA/RPS
›«« Œμ°33.3 g/L« ÛμŒ ¶¤» ›«∏Ÿ ∑∫ ÃØ°
≥Ì»Ÿ. ◊Ø™50.0 g/LÕ Ò≥œ© ı Ù∫ ÛμŒ100.0 g/L
« ÛμŒ ¶¤»PMMA/RPS ›«°≠ Œμ° ı Ù‘ ™¬ Õ
∫ Ø× ·˙ß. à ˆÛ∫PMMA« Ûμ° ˆ™°‘ Ù∏È
√·« ب∫à ˆÿ˜ ∑ΔÆ Œ°» –¬˜° «ÿ ›«Ã ÷Ó ˆ‚ ∏Ÿ¬ ˙ÓÆ ˆÆ‚ ßÆ∏Œ ¸˚«˙Ÿ. ◊Ø«Œ ¤∫ –
¬˜°≠μPMMA/RPS ˛∫ ¸º˚∏Œ ’≠à fl˝«˙Ì –¬
˜° ı°“ˆœPMMA ˛Ã Ê‘ √Ó™ ˆ»Ÿ. ÃŒ Œÿ100.0 g/L« ÛμŒ ¶¤»PMMA/RPS¬ –¬˜° Ÿ√0∏Œ ∏π«
ıÛμ –¬¿∫ Ÿ• √·È˙¬ fiÆ ‚Û¬Œ ∏π«ˆ
“Ÿ. ÃØ— Ø∫ ßÆ°100.0 g/L« ÛμŒ ¶¤»PMMA/RPS
¬ –¬¿ ∞˙Œ≠ ∞Îœ¬ Õà ˚’œˆ Ÿ. —Ì33.3 g/L
« ÊÏ £§50.0 kPa ¸§ƒ« –¬˜°≠ ›«Ã ƒ´«¬ ˆÛ à ™∏μŸ. ◊ Ãج ⁄√» ∑« Œ≤° ´ „‚ ßÆß. Ã
° Òÿ50.0 g/L« ÛμŒ ¶¤»PMMA/RPS¬50.0 kPa°≠μ
◊Û »§» –¬¿ª ∏¥Ÿ. ◊Ø«Œ50.0 g/L Ûμ«PMMA
Œ ⁄√»PMMA/RPS ›«∫ ª ¨∏°≠ Áλ3≥« √·È
fl –∫ –¬¿¸ß, ¿« »§∫, Œμ¶ Ì¡“ ß –¬
¿ ∞˙Œ≠ °Â ˚’‘ª À ˆ ÷˙Ÿ.
PMMA/RPS ›«« –¬¿« Œμ¶ ·§œ¬ Ε˚Œ ¥ μ¬ ›«« ∫∫ˈß. Ô ∫∫ˈ ™Ã ¨ˆœ Œ°«¬ ‹Œ
˚° Η ˙◊∫à ø –¬¿« Œμ¬ ∑Δ¯Ÿ. ª ¨∏°≠
¬ à ™Èª ∏œ‚ ßÿ ƒ(1)ª ÃÎœ©Fig. 5°≠ ∏©≥¯
«Ë∏Œ Ú∫ •ÃÕ °Èª ÷˚≠ œ¥Ì, ◊ ·˙¶Fig. 5°
«±∏Œ ™∏ª˙Ÿ. ◊ ·˙PMMA° ⁄√«ˆ ∫RPS ›«
« ∫∫ˈ¬1.82 MPaà ÚÓ≥Ÿ. ð Òÿ100.0, 50.0, ◊Æ
Ì33.3 g/L«PMMA ÛμŒ ⁄√»PMMA/RPS ›«È∫0.08, 3.55, ◊ÆÌ2.18 MPaà ¢¢ ÚÓ≥Ÿ.
ª ¨∏°≠¬ –¬˜° ¨”˚∏Œ Øœ¬ ø»PMMA/RPS
›«ª ÃΗ §∂Ø æ≠« ø˚ –¬¿ Ø∫μ ∂Áœ¥Ÿ. Fig. 6(a)¬ Œß˚∏Œ Ø≠√≤PMMA/RPS ›«« Á‹° …∞
–¬˜ RP¶ ¸∂ –¬æ≠Œ ¯§— ·˙ß. Ê˙√£Ã0- 420 sÓˆ RP¬0.0 kPaŒ ؈«˙Ì, 420 s°≠40.3 kPaŒ
Û¬«˙Ÿ. ◊ÆÌ1020 s°≠0.0 kPaŒ Ÿ√ ∏π» ƒ1,500 s
Óˆ ◊ÎŒ ؈«˙Ÿ. Fig. 6(b)¬Fig. 6(a)Õ øœ— –¬Ø≠
œ°≠50.0 g/L« ÛμŒ ⁄√»PMMA/RPS ›«∏ŒŒÕ ¯§
» –¬¿ÃŸ. ◊≤˙ ∞à RP°0.0 kPaœ ß ›«« –¬
¿μ ¯Ÿ°, 40.3 kPaŒ ı°«˙ª ß-44.6%« –¬¿ª ∏
¥Ÿ. ◊ÆÌ Ÿ√0.0 kPaŒ RP° ∏π«˙ª ß –¬¿μ
‚Û¬Œ œ¸˜ ∏π«˙Ÿ. ÃØ— ·˙¬ ª ¨∏°≠ ¶¤—
PMMA/RPS ›«ª ∞Η §∂Ø –¬æ≠° ¨”˚Œ –¬˜
Ø≠° Îÿ≠μ ø˙˚Œ –¬ ¿ª ∏”ª ™∏ΩŸ. ◊Ø™
Fig. 6(b)¬ ‹ˆ –¬¿ª ™∏æ ”ÃÁ, ÃÕà –¬˜Œ≠ ∏
§«ˆ “‚ ßÆ°Fig. 6(a)Õ¬ ˜¢˚Œ Ò≥¶ “ ˆ ¯Ÿ.
◊°≠Fig. 6(b)« Ó±ª Fig. 5°≠50.0 g/LŒ ⁄√»
PMMA/RPS ›«∏ŒŒÕ Ú∫ ÷˚≠» ‘ˆ¶ ÃÎœ© ∏§œ
¥∏Á, ◊ ·˙¶Fig. 6(c)° Ω∫ «±∏Œ ™∏¬Ÿ. «—Fig.
6(c)°¬ Ò≥¶ ßÿFig. 6(a)« –¬ Ó±ª „∫ «±∏Œ ‘≤
™∏¬Ÿ. ◊≤˙ ∞à §∂Ø æ≠ŒŒÕ ¯§» –¬ Ó±∫ ¸∂
–¬æ≠Œ ¯§— Ó±˙ ¸›˚∏Œ øœ— Ê‚« ¿‰ª ∏¥
Ÿ. Ÿ∏ °Â Ù∫ –¬˜°≠ ¸∂ ™40.3 kPa∏Ÿ5.7 kPaÃ
´46.0 kPaà §∂Ø –¬æ≠ŒŒÕ ÚÓ≥Ÿ. à ¿˜¬ ª ¨
∏°≠ ¶¤— æ≠√∫¤, PMMA ⁄√˝ ÓÃ Δ˜ ÷˚≠«ˆ “‚ ßÆ° ™∏≠ Õ∏Œ ∏ŒŸ. ؘFig. 5°≠ °ØŸŒ •
√— ŸÕ ∞à √·ª ß°£« Ò’˙∫° «ÿ °«¬ –¬
¿« “ÆμÕ √ƒπë°≠ Áλ ˜∞›ÁÈ « Œ§Æ∫
ÓÃ´μ‚ª÷¬Õ∏ŒÁ·»Ÿ. ÃØ—‰ŒªÌ¡œÌ≥±—
ŸÈFig. 6(c)°≠«¿˜¬Ê–˜“…ˆ÷ªÕ∏Œ‚λŸ.
Fig. 6. (a) Reference curve measured by a commercial pressure sensor for ?P adjusted by hands, (b) the dynamic response curve to the pressure measured using a fiber-optic sensor with a PMMA/RPS diaphragm, and (C) a comparison of the reference curve (thin line) and calibrated response curve (thick line).
5. ·–
RPS ›«Ã Ãλ §∂Ø –¬æ≠« ´ ‹°fl« œ™Œ ¿
¸ß« ˘“ƶ¶ ÿ·œ‚ ßÿ, PMMA/RPS ›«ª ÃΗ æ
≠¶ ¶¤œÌ ◊Õ« –¬ ¿ Ø∫ª ∂Áœ¥Ÿ. ◊ ·˙RPS
›«Ã 20 kPa §μ« –¬˜Óˆ ¯§ °…fl¯ ›È°
PMMA/RPS ›«∫50 kPa ÃÛ« –¬˜μ ¯§“ ˆ ÷˙Ÿ. 50.0 g/L« Ûμ¶ Æ¬ PMMA Î◊ª ÃÎœ© ¶¤»
PMMA/RPS ›«∫ ÷˚« ¿ ŒμÕ »§∫ª ∏¥Ÿ. ¶¤
» æ≠¬ ̧» –¬”∏ ΔœÛ ø˚ –¬Ø≠° Îÿ≠μ ∫¯
˚∏Œ ¿œ¥Ÿ. Ÿ∏ –¬˜° ÙΔ˙ˆœ ¯§ –¬™« ¿˜
° øˆ¬•, ö ÷“≠œ‚ ßÿ≠¬ æ≠√∫¤˙ √· ¶¤«
÷˚≠, ∏Ÿ §Æ— Ö˚ « ˆ≥à ‰‘ª μ‚œ¥Ÿ.
ÃØ— ƒ”¨∏¶ ≈£ŸÈPMMA/RPS ›«ª ∞Η §∂Ø –¬æ≠« «Î≠ °…∫à ø˙ Õ∏Œ ‚λŸ.
Á« ¤
à ÌÆ∫2011‚μ §Œ(≥∞˙–‚˙Œ)« Á¯∏Œ —π¨∏
Á‹« ‚ ¨∏Á˜ ˆ¯ª fiΔ ˆ‡» Õ”(2011-0023953)
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