What is an Optical Notch Filter and What Do They Do?

Optical notch filters are devices designed to attenuate light within a specific wavelength range to a very low level while transmitting most wavelengths with little intensity loss. Other names for optical notch filters include band-rejection or band-stop filters.  They do the opposite of bandpass filters, a different type of filter that provides high out-of-band rejection […]

Why Notch Filters Are Essential in The Coating Industry

Notch filters, otherwise known as band-rejection or band-stop filters, are a type of optical filter designed to selectively reject a wavelength band and transmit at both longer and shorter wavelengths. Notch filters are often used throughout the coating industry to create components for various technological and scientific applications such as raman spectroscopy, laser-based fluorescence instrumentation, […]

What Are Neutral Density Filters?

A neutral density (ND) filter is a darkened glass affixed to a lens. This filter between the subject and the imaging tool reduces light wavelengths so that colors are not overexposed. ND filters only affect light, not color reproduction, sharpness, or contrast. We’ll explain in more detail how ND filters work, the various types of […]

What Are Thin-Film Optical Filters?

Usually attached to a substrate like glass, thin-film optical filters are layers of materials with optical properties. These filters change the direction of light as it passes through them, creating internal interferences. Filters can be specially designed to transmit, reflect, or block light in any wavelength between ultraviolet (UV) and infrared (IR). Thin-film optical filters […]

Considerations for Selecting AR Coatings

Anti-reflective (AR) coatings are optical coatings that decrease the amount of light reflected off a surface. Commonly applied to lenses, mirrors, or glass barriers, AR coatings are designed to maximize the throughput of light, while reducing hazards caused by reflections. This ability makes AR coatings an ideal solution for optical instruments, imaging devices, cameras, telescopes, […]

What’s the Difference Between Anti-Reflective and Anti-Glare?

“Anti-reflective” and “anti-glare” are common terms related to coating, but they are each distinct and provide different benefits. Depending on a particular application, an anti-reflective or anti-glare coating may be appropriate to use. Knowing what separates these two concepts can help determine which is best to use for a given coating. Here, we’ll review the […]

An Introduction to the Different Types of Optical Filters

Optical filters are passive optical devices that consist of specialized optical coatings applied onto a substrate. The coatings modify the refractive index of the substrate, enabling them to reflect, transmit, or absorb incoming light depending on its wavelength. This quality is useful for various optical tools and systems, such as chemical analysis units and microscopes. […]

Design Guide for Thin Film Coatings

Thin film coatings, such as antireflective (AR) coatings, are made from various materials, such as metals, oxides, and compounds, and are deposited in layers onto a substrate. Thin film coatings can be deposited in both single and multiple layers, and the configuration you choose determines how it will manipulate different wavelengths of light. Thin film […]

Applications of Optical Microscopes

Optical microscopy is a technique that allows the viewing of samples more closely using optical microscopes. It relies on light and one or more lenses to magnify samples. Optical microscopy is remarkably versatile, increasing the detail and contrast of a microscopic specimen. A range of applications rely on simple and complex microscopy techniques. Fluorescence Fluorescence […]

Ion Beam Sputtering

Ion Beam Sputtering Coating (IBS) uses an ion source to deposit or sputter a thin film onto your targeted material to create a dielectric film. Since an ion beam is mono-energetic and collimated, it creates a very precise control over the thickness of the film. Since an ion beam is mono-energetic and collimated, it creates […]