Single Cavity Filter Tutorial
The Single Cavity Filter (SCF) is used to select a single frequency from a broad spectral range. SCFs are typically used for…
Linear Transmittance Filter Tutorial
Linear Transmittance Filter (LTF) has a transmittance that is changing linearly over a specified wavelength range. LTFs are typically used for…
CWDM Filter Tutorial
Coarse Wavelength Division Multiplexing (CWDM) filters are designed to multiplex and de-multiplex wavelength signals in metropolitan, access and enterprise networks and for Cable TV applications. In addition…
Tap Coupler – Beamsplitter Tutorial
Tap couplers filters and beamsplitters are used to reflect a specific percentage of incident light over a broad wavelength range and for a specified angle of incidence. Beamsplitters and tap couplers can be specified…
Gain Flattening Filter (GFF) Tutorial
Gain Flattening Filter (GFFs), also known as gain equalizing filters, are used to flatten or smooth out unequal signal intensities over…
Optical Interconnects for Data Centers- Lighting the Cloud
Introduction As data storage and computing resources move into the cloud the demand on data centers for storage and data transfer capacity has increased dramatically over the last decade (ref. 1). Stored data needs to be accessed and transferred constantly to and from...Edge Filters for Raman Spectroscopy
Raman spectroscopy probes the molecular vibrational and rotational modes of a material in order to detect and identify the material. Typically, laser light is incident upon the material and the scattered light is measured.
The excitation source (laser line) intensity is often to orders of magnitude greater than the Raman scattered signal. Therefore, edge pass (or notch) filters are required to block the Rayleigh scattered laser light while transmitting the red-wavelength shifted (Stokes) and/or the blue-wavelength shifted (Anti-Stokes) Raman scattered signal.
Handheld Raman vs “Fingerprint” Applications and the Different Optical Filters that Enable Them
Raman spectroscopy is a powerful and increasingly ubiquitous analytical tool capable of identifying molecular constituents of samples under test and, when combined with microscopy, exploring specific cellular structures and functions. Non-invasive, non-contact, requiring no sample preparation or chemical tagging – it is no wonder that Raman has established a presence as an invaluable analytical technique both in labs and in the field.
Large Format Narrow Bandpass Filters – A Uniformity Challenge
1 Introduction Large format (>100 mm diameter), narrow bandpass filters (NBPF) are required in many fields. Applications requiring a large field of view drive the need for large collection optics, however high wavelength selectivity provided by narrow,...Optical Filters for Sensors and Detectors
Clear the Air: New Optical Filters for Sensors and Detectors Environmental air quality; proximity control; crowd counting; climate change; the “Internet of Things”. Our world has become an increasingly monitored place where the proliferation of sensors and detectors...Eyes in the Skies- Optical Filters for Earth Observation
“Measurement is the first step that leads to control and eventually to improvement. If you can’t measure something, you can’t understand it. If you can’t understand it, you can’t control it. If you can’t control it, you can’t improve it.”
The Right Filter for MWIR Equipment
Utilization of mid-wavelength, also called midwave, infrared (MWIR) light is critical in many areas, including thermal monitoring of equipment and homes; gas absorption; military enhanced-vision systems for imaging vehicles, people, and terrain; and environmental monitoring of gases. Even diagnosis of pregnancy in dairy cows, among other applications, can productively use infrared in the MWIR range.