AC254-125-A-ML In Stock

The AC254-125-A-ML by ThorLabs is an achromatic doublet that serves as the perfect solution for controlling chromatic aberration in an optomechanical setup. The AC254-125-A-ML comes pre-mounted in an engraved threaded mount housing, making it easy to integrate into a setup and start achieving diffraction-limited spots with monochromatic sources like lasers.

The AC254-125-A-ML is optimized for use in the visible spectral region (400 nm - 700 nm) and has been computer optimized at infinite conjugate ratios for optimal performance. Its achromatic doublet has been designed using the hydrogen "C" (656.3 nm, red) lines, hydrogen "F" (486.1 nm, blue/green), and helium "d" (587.6 nm, yellow) which are commonly used to define the Abbe Number, Vd, of a material. This makes the AC254-125-A-ML an excellent tool for controlling chromatic aberration.

The engraved arrow on the Ø1" diameter of the AC254-125-A-ML indicates the antireflection coating that can be found on the surface, focal length, and the part number. This allows the user to easily identify and use the lens in a setup. An arrow points to the curved side of the lens from the flat side, indicating that for proper collimation to occur, light should travel in that direction. This is because the curvature of each side has a different radius and should be respected for optimal results. When focusing a collimated beam, simply point the engraved arrow in the opposite direction of light propagation. Finally, the infinited conjugate ratio is distinguished with an infinity symbol on the surface of the lens. The process of aligning parallel beams of light radiating from a single source is called collimation and can be easily accomplished by placing the light source one focal length away from the flat side of a lens. This will result in straightened rays being emitted from the curved side.