Educational Materials

Transition width and edge steepness are two terms often used to describe the spectral properties of edge filters and it is important to know that these two terms are related, but not interchangeable. Transition Width is the maximum distance between the laser line (where OD > 6) and the 50% transmission point. Edge Steepness is the actual steepness measured from the OD 6 point to the 50% transmission point. Learn More

All Semrock filters are hard coated with sophisticated Ion Beam Sputtering (IBS) technology, resulting in patented state-of-the-art filters with extremely durable hard glass coatings on a single hard glass substrate. No absorbing glass and no lamination is necessary. The result is exceptionally durable "no burn out" fluorescence filters of the highest performance. Learn More

All Semrock filters are inspected in accordance with industry standards established for optical components. Learn how our team inspects each filter. Learn More

The "color" of light is generally identified by the distribution of power or intensity as a function of wavelength λ. Visible light has a wavelength that ranges from about 400 nm to just over 700 nm. Sometimes it is convenient to describe light in terms of units called "wavenumbers," where the wavenumber w is typically measured in units of cm-1 ("inverse centimeters") and is simply equal to the inverse of the wavelength, and is therefore proportional to frequency. Learn More

In many high-performance Raman systems with microscopic imaging capabilities or highly sensitive remote probes it is desirable for the excitation laser beam and the Raman-shifted signal light to share a common light path. Illustrations in this tech note describe the two layouts and the ideal filters for each system. Learn More

Semrock uses individual PET-G packaging for standard-size catalog filters. This packaging allows Semrock to keep the parts cleaner, reduce potential defects caused by shipping & handling, and utilizes 100% recyclable PET materials. Learn More

The RazorEdge edge filters and the StopLine notch filter are both available with OD>6 blocking of the laser line. Should you use an edge filter or a notch filter to block the laser line in your Raman system? Learn more. Learn More

High-performance optical mirrors are a key component to most system designs. From bench-top setups to high-end lab instrumentation, mirrors can enable a reduced system footprint, combine multiple sources, help to form images, or other purposes. This article provides a high-level, basic overview of some of the key specification parameters to consider when selecting the appropriate mirror for your optical system. Learn More

Sharpen your optical filter knowledge with our 12-part lecture series on filters. Presented by Turan Erdogan, PhD, these lectures were a part of a day-long group presentation. Learn More

The Kola Deep spectral measurement system brings Optical Density (OD) theory into measurement reality. Our engineers developed a proprietary new system that allows for proven measurement of the steepest and deepest spectral features of Semrock-brand Optical Filters, ensuring your instrument will deliver best-in-class sensitivity. Learn More