{"product_id":"bp1640-25","title":"BP1640-25 Bandpass Filter(CWL=1640nm,FWHM=25nm)","description":"\u003cp data-path-to-node=\"0\"\u003eThis BP1640-25 bandpass filter is designed to transmit a moderately narrow short-wave infrared (SWIR) band centered at 1640 nm while strongly reducing unwanted out-of-band light.\u003c\/p\u003e\n\u003cp data-path-to-node=\"1\"\u003eBecause the 1640 nm wavelength range perfectly overlaps with the strong optical absorption band for methane (CH4) and other specific hydrocarbon bonds, this filter is highly suitable for SWIR gas sensing, optical gas imaging (OGI) for leak detection, environmental monitoring, and industrial machine vision. It helps precisely isolate the target methane absorption signature, strongly reduce broad ambient thermal and illumination background noise, and preserve exceptionally high signal brightness for high-contrast, sensitive measurements.\u003c\/p\u003e\n\u003cp data-path-to-node=\"2\"\u003e\u003cb data-path-to-node=\"2\" data-index-in-node=\"0\"\u003eKey specifications:\u003c\/b\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eWavelength \/ main spec: 1640 nm center wavelength (CWL)\u003c\/li\u003e\n\u003cli\u003eBandwidth \/ transition spec: 25 nm FWHM\u003c\/li\u003e\n\u003cli\u003eTransmission \/ blocking: T \u0026gt; 95%; OD4 blocking from 800–2000 nm\u003c\/li\u003e\n\u003cli\u003eFormat \/ availability: Available in 12.5 mm to 25 mm diameters (mounted and unmounted options)\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SyronOptics","offers":[{"title":"CWL=1640nm \/\/ FWHM=25nm \/ OD4@800-2000nm \/\/ T＞95% \/ dia12.5mm(unmounted)","offer_id":51071861293339,"sku":"SO3014848-d12.5u","price":115.0,"currency_code":"USD","in_stock":true},{"title":"CWL=1640nm \/\/ FWHM=25nm \/ OD4@800-2000nm \/\/ T＞95% \/ dia12.5mm(mounted)","offer_id":51219871498523,"sku":"SO3014848-d12.5mt","price":115.0,"currency_code":"USD","in_stock":true},{"title":"CWL=1640nm \/\/ FWHM=25nm \/ OD4@800-2000nm \/\/ T＞95% \/ dia25mm(unmounted)","offer_id":51219871531291,"sku":"SO3014848-d25u","price":145.0,"currency_code":"USD","in_stock":true},{"title":"CWL=1640nm \/\/ FWHM=25nm \/ OD4@800-2000nm \/\/ T＞95% \/ dia25mm(mounted)","offer_id":51219871564059,"sku":"SO3014848-d25mt","price":145.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0759\/8755\/0491\/files\/BP1640-25_Bandpass_Filter_CWL_1640nm_FWHM_25nm.webp?v=1780950865","url":"https:\/\/syronoptics.com\/products\/bp1640-25","provider":"SyronOptics","version":"1.0","type":"link"}