A plano-concave cylindrical lens has curvature in the vertical direction, functioning as a concave lens, while having no curvature in the horizontal direction. It is used to magnify a beam in a single direction, such as transforming a laser beam into a line or sheet of light, or altering the height of an image without changing its width. When combined with a concave cylinder lens, it can be used to shape the elliptical beam of a semiconductor laser into a circular one, among other applications. Features of Plano Concave Cylindrical Lens The cylindrical concave lens forms a diverging line-shaped virtual image and is primarily used to control the size of a beam in one direction. This lens consists of a flat surface and a concave cylindrical surface, with a negative focal length. Light passing through the axial meridian does not experience a change in convergence, but light passing through the refractive meridian does experience a change in convergence. Applications of Plano-Concave Cylindrical Lenses Beam Shaping: Plano-concave cylindrical lenses are often used to convert collimated laser beams into line beams. By orienting the curved surface of the lens towards the light source, spherical aberration can be minimized, thereby achieving beam shaping. Image Shaping: A pair of plano concave lenses can be used for image shaping, particularly when it is necessary to shape a point source in one-dimensional direction. Laser Scanning Systems: In laser scanning systems, about plano concave lens are used to adjust the beam shape to meet scanning requirements. They can also be combined with other optical elements to achieve complex beam shaping functions. Spectral Analysis: During spectral analysis, plano-concave cylindrical lenses are used to adjust the divergence or convergence angle of the beam to meet different measurement needs.
