When an optical system needs to transmit one wavelength range and suppress another, both interference filters and colored glass filters may appear to solve the same problem. They do not, however, control light in the same way. A colored glass filter primarily relies on wavelength-dependent…
Extinction ratio is the ratio between the transmittance a polarizer gives to the polarization state it passes and the transmittance it gives to the orthogonal state it is meant to block, at a stated wavelength, angle of incidence and aperture. A part specified at 1000:1…
Cube Beamsplitter vs Plate Beamsplitter: Which Design Is Better for Your Optical System? Neither a cube beamsplitter nor a plate beamsplitter is universally better. A cube usually simplifies mechanical alignment and, in its normal-entry geometry, avoids the lateral displacement associated with transmitting through an angled…
Choose fused silica when the window must work in the deep UV, must not disturb polarization or wavefront, or must survive fast thermal transients; choose sapphire when the window faces abrasion, high pressure, chemical attack or high temperature, or when the band extends past roughly…
When specifying a mirror, beamsplitter, filter, or other coated optical component, choosing between a dielectric coating and a metallic coating is not simply a question of which one has higher reflectivity. The two coating families produce optical behavior through different physical mechanisms. Metallic coatings are…
A telecentric lens keeps image magnification essentially constant while the object moves along the optical axis, within a defined telecentric range. A conventional imaging lens does not: as the object moves closer or farther, its image grows or shrinks. That single difference decides most selection…
Choosing a fluorescence filter manufacturer is not simply a matter of ordering a filter at a nominal wavelength. A fluorescence optical system must separate relatively strong excitation light from the fluorescence signal that the detector is intended to measure. The required filter therefore has to…
Choosing a precision optical components manufacturer is mostly a question of process control, not company size. A supplier that builds to your drawing has to control three things that determine whether the part works in your system: the geometry produced by fabrication, the spectral behaviour…
Precision Micro-Optics Custom C-Lens for Fiber Collimation and Optical Communication A C-Lens is a compact cylindrical micro-optic used for fiber collimation, optical coupling and fiber-to-free-space beam interfaces. Its spherical optical surface provides the refractive power required to control the beam, while the opposite end can…
Choosing an F-theta scan lens manufacturer is not simply a matter of matching a lens to a laser wavelength. An F-theta lens works as part of a complete scanning system. Its practical performance depends on the laser wavelength, input beam diameter, effective focal length, galvanometer…
Selecting a polarizing filter for machine vision glare reduction starts with one question that has nothing to do with the filter itself: is the glare a specular reflection from a dielectric surface, or from bare metal? Dielectric glare — plastic, glass, paint, wet surfaces, film…
Choosing a Raman longpass edge filter should start with two numbers: the excitation laser wavelength and the lowest Stokes Raman shift you need to measure. The nominal cut-on wavelength alone is not enough. A useful Raman edge filter must simultaneously provide strong rejection at the…
