For collimation or focusing tasks, a very broad and complete line of fiber optic components is available for coupling light into and out of optical fibers. Depending on the fiber’s core and cladding diameter and the required optical performance, the user can choose from a wide range of sizes from micro to large beam versions.
Featuring low back reflection and diffraction-limited lenses, these fiber collimators, focusers and combiners exhibit high throughput and high optical performance, for example with focal spot sizes down to a few microns.
Laser Diode to Fiber Couplers
Receptacle style laser diode to fiber couplers have a female receptacle, such as NTT-FC or AT&T-ST, etc., at the output end of a small, rugged package, while pigtail style laser diode to fiber couplers with a fiber pigtail permanently fixed to the collimator provide higher coupling efficiencies and lower backreflection levels as well as better stability.
Both laser diode to fiber coupler series may be purchased pre-aligned, with the diode already in place, or as a kit that can be assembled by customers using their own diode. These tilt-adjustable laser diode source couplers work with MM, SM and PM ﬁber and are available in different diameters for a variety of diode case sizes and for diode wavelengths from 375 nm to greater than 2050 nm.
Laser diode power combiners (receptacle or pigtail style) are designed to combine two polarized laser diode outputs into a single SM, MM or PM output fiber. Additionally, these series includes fiber-to-fiber polarization combiners/splitters as well as laser diode to fiber couplers with a monitor photodiode that either measures the reference power from the laser diode or detects light returning from the fiber.
Fiber to Photodiode Couplers
Fiber to photodiode couplers are available for virtually any photodiode on the market, using either SM, MM or PM fiber. The coupler design is both rugged and flexible, allowing users to do their own alignment if desired. For OEM applications, miniature pigtail style fiber to photodiode couplers that do not use the tilt adjustment technique provide both a smaller size and lower cost.
Laser to Fiber Couplers
Receptacle style, non-contact style laser to fiber couplers feature an air gap between the fiber and the lens, allowing to adjust the distance between them. They are best suited for applications where either the input energy is higher than 400 mW, or when more than one wavelength is to be coupled into the fiber, or for input beams that have unusually large beam diameters or divergence angles.
Adjustable focus source laser to fiber couplers, available with a variety of lens types and fiber types, are ideal for situations where optical coupling efficiency is critical, such as in high-power applications. A special connector allows the spacing between the fiber and lens to be precisely controlled without rotating the fiber – ideal in polarization maintaining applications, as the polarization axis does not change.
Pigtail style laser to fiber couplers are recommended for permanent or semi-permanent situations. The permanently glued fiber-lens assembly is inserted into a tilt adjustment flange and held in place with two radial set screws. In these pigtail style couplers, the internal endface of the fiber is polished at an angle to reduce backreflection, which can further be improved by adding an AR coating to the inner fiber tip.
RGB (Red/Green/Blue) combiners and delivery systems efficiently combine three to five visible lasers into a common output port – providing a complete method to deliver full color laser light from a SM, PM or MM fiber. The RGB combiners can be provided as a pigtailed passive device or as a low profile RGB laser engine with or without built-in laser diode drivers.
You are looking for a special lens material, a particular optical fiber type or a certain fiber length? We would be pleased to specify and source a customized light to fiber coupling or collimating solution for you – please contact us!
Beyond light to fiber couplers and collimators, further fiber components are available like fiber receptacle collimators and focusers, fiber connectors, mating sleeves and adapters, fiber WDMs, combiners, splitters and couplers, fiber amplifiers, attenuators and polarization controllers, as well as fiber optic circulators, delay lines, filters, isolators, switches and other fiber optic assemblies.
Our portfolio of precision optics includes optical lenses, optics assemblies, optical filters, optical prisms, optical mirrors, optical beamsplitters, etalons, optical gratings, optical isolators and polarization optics as well as optical scanners and deflectors or optical modulators, q-switches and pockels cells.
For mounting, adjusting and moving our optical components with high precision, we carry an array of optomechanics and motion control such as optical mounts, rotary and translation stages plus motion controllers as well as optical tables, breadboards and platforms.
Light to fiber couplers and collimators can be used to couple light to/from lasers, laser diodes, acousto-optic devices, photodiodes and other fiber optic devices, and are additionally ideal for fiber packaging applications.
While pigtail style versions are firmly connected to the optical fiber by the manufacturer (so the fiber cannot be replaced without also replacing the coupling lens), receptacle style versions with plug terminals for a variety of optical connectors allow for a user-detachable fiber connection.
Pigtail style light to fiber couplers provide optimum coupling efficiency and output stability with minimum insertion loss and backreflection. In these couplers, the fiber tilt is pre-adjusted, and the fibers are pre-aligned and permanently glued to the focusing lens. The output fiber can be terminated with different output connectors.
Receptacle style, non-contact style light to fiber couplers always show an air gap between the fiber and the lens – with some models allowing for adjustment of the fiber/lens distance to compensate for changes in source wavelength or to intentionally defocus the light beam to prevent arcing in high-power laser to fiber applications. Non-contact style couplers also have superior polarization maintaining capabilities compared to physical contact style couplers. However, the backreflection level for the endface of the fiber is quite high because of the air gap – slant polishing both fiber ends to deflect the backreflected signal can help. Tilt adjustment capabilities allow for optimum alignment of optical paths.
Receptacle style fiber to photodiode couplers commonly consist of two baseplates (one holding the photodiode and the other one containing the focusing optics and the connector for the input fiber), separated by an O-ring. Tilt adjustment allows to achieve the maximum coupling efficiency. With pigtailed fiber to photodiode couplers, the fiber, lens and photodiode are glued into a single assembly without tilt adjustment – or the couplers use no lens at all, and the fiber is simply butted against the photodiode. Both of the latter designs are intended for OEM applications.
Laser diode power combiners are special devices for combining two or more laser diode outputs into a single fiber. Laser diode combiners/splitters utilize a beam splitter in reverse to act as a combiner. The laser diode outputs are collimated and attached onto the combiner and the combined beam is focused into the splitter/combiner output fiber. Rotating the collimated outputs helps maximizing the light output. These combiners can also be equipped with photodiodes that act either as a reference laser diode power monitor or as a detector for light returning from the fiber. Such a setup is also known as optical transceiver.
RGB combiners and delivery systems combine light from multiple different wavelength sources (most commonly red, green, and blue) to achieve output light in a single fiber that is white in appearance. A broad spectrum of colours can be generated by varying the relative intensities of the individual light sources.
Alternative Terms: Laser Diode to Fiber Coupler; Laser Diode to Fiber Collimator; Laser Diode to Fiber Combiner; Laser to Fiber Coupler, Laser to Fiber Collimator; Laser to Fiber Splitter; Laser to Fiber Combiner; RGB Combiner; RGB Delivery System; Photodiode to Fiber Coupler; Fiber to Photodiode Coupler