Focusing lens element GCO-15 series

laserprecision

Air-spaced focusing lenses are designed to focus the high-power radiation emitted by lasers. The lenses are optimized for high precision applications such as used in laser machining systems for welding, cutting, drilling and strutting. They can also be used for collimating the laser beam delivered by fiber. The Daheng’s air-spaced focusing lens product utilizes high quality triple lens elements which are optimized to obtain a diffraction-limited focus spot. With the design-specific optical coating, the lens system achieves transmission throughout at a designed wavelength up to 98%. Spot size Dspot (1/e2) The minimal possible focus spot size from an air-spaced focusing lens is calculated by the wavelength of the laser multiplied with the focal length of the lens, f', the FAP factor and the diffraction value M2 of the laser beam, and divided by the beam diameter Dbeam(1/e2). Daheng Depth of focus The depth of focus of an air-spaced focusing lens is defined by a doubled Rayleigh length. The Rayleigh length describes as a distance, along the optical axis, between the positions where the beam area is doubled in front of or behind the focal position. The Rayleigh length ZR is calculated by the beam area in the focal plane multiplied with a factor (depending on the FAP-factor) divided by the wavelength and the diffraction value M2 of the laser.