Cylindrical lenses focus or expand light within a single axis only. N-BK7 cylindrical lenses are manufactured from fine annealed glass and polished to tight tolerances to meet the demanding requirements of applications including line illumination for metrology, laser scanning, spectroscopy, and diode laser beam shaping.
- Fine annealed N-BK7 optical glass
- ≤Λ/2 surface irregularity in Y, Λ/4/cm in X
- 40-20 scratch-dig
- Broadband or laser line AR coatings
- Standard sizes and focal lengths
- Available in both round and rectangular shapes
Precision Optical Quality
Our N-BK7 precision cylindrical lenses are designed to meet the demanding requirements of laser electro-optic applications. They are manufactured from fine annealed optical glass and are polished to tight tolerances to ensure minimum wavefront distortion. Tight surface quality tolerances minimize scatter and unwanted diffraction effects, making these lenses especially well suited for sensitive laser applications, including laser scanning, diode laser beam shaping. Additional applications include focusing light into a thin line for optical metrology or collecting light in spectroscopy systems. They can also be used to expand the output of a laser diode into a symmetrical beam.
Illustration of using two cylindrical lenses at right angles, with different focal lengths, to achieve collimation with different effective focal length for each axis. Circularize a Laser Diode Beam Profile
In a typical laser diode (a P-i-N diode), electrical current flows vertically between contacts on top of and below the semiconductor material substrate. Charge carrier combination and the resulting light emission occurs in the intrinsic region between the doped electrodes. A horizontal optical cavity is formed by cleaving the substrate and polishing the side faces. Fresnel surface reflections at these faces create optical feedback resulting in a lasing effect. Light emitted from a rectangular aperture typically takes on an elliptical beam profile with angle θ1 and θ2 along the major and minor axes. Two cylindrical lenses with focal lengths f2/f1 = θ1/θ2, each positioned their focal length away from the laser diode, may be used to produce a circular collimated beam output.
N-BK7 is an excellent material for most visible and near infrared applications. It is the most common optical glass and provides great performance at a good value.
Broadband Visible Antireflection Coating
Our AR.14 broadband multilayer antireflection coating markedly improves the transmission efficiency of these lenses by reducing surface reflections over a 430-700 nm wavelength range. This AR coating performs effectively for multiple visible wavelengths and tunable lasers eliminating the need for several sets of optics.
Broadband Multilayer NIR Antireflection Coating
Our AR.16 multilayer anti-reflection coating is recommended for NIR applications in the 650-1000 nm range.
1064 nm Laser Line Antireflection V-Coating
Our AR.33 laser line V-coating offers the lowest reflectance at 1064 nm for maximum transmission while maintaining high durability and high damage resistance. Valuable laser energy is efficiently transmitted through the plano-convex lens rather than lost to surface reflection and scattering. The trade off to its superior performance is the minimal laser line wavelength range.
Mounting Cylindrical Lenses
We offer a wide selection of cylindrical lens mounts for incorporating your lens in an optical system.